The US secretary of state said Assad's reign "is coming to an end," a vision Russia's foreign minister did not indulge in. Russia has vetoed a UN Security Council resolution to probe a chemical weapons attack in Syria.
"I expressed the view that the current state of US-Russia relations is at a low point. There is a low level of trust between our two countries. The world's two foremost nuclear powers cannot have this kind of relationship," Tillerson told reporters after the meeting.
Lavrov alleged that attempts had been made to "prevent us from cooperating and even raise tensions," without referring to the catalyst.
"We believe that this approach is short-sighted, particularly because history has shown that when Moscow and Washington cooperate, not only our peoples but the whole world benefits from it," he added.
Lavrov and Tillerson announced the establishment of a task force comprising foreign policy officials charged with addressing issues and making progress toward stabilizing relations. But the fate of Syrian President Bashar al-Assad remained a divider, with both sides backing opposite visions.
US missile attack on Syrian airbase
US forces fired a barrage of missiles on a Syrian airbase days after it theatened the Syrian government in the United Nations. The launch came in response to an alleged toxic gas attack on civilians.
Image: picture-alliance/AP Photo/US Navy/S. Price
59 Tomahawk Missiles
In April, US forces attacked a Syrian air base with cruise missiles in retaliation for a deadly chemical weapons attack on Syrian civilians. The US attack killed several Syrian soldiers and almost completely destroyed the base.
Image: picture-alliance/AP Images/US Navy/F. Williams
Syrian air base
The air base Al-Shairat looked like this before 59 Tomahawk rockets were fired at the site. US President Donald Trump said this was the base from which the poison gas attack was flown out of on Tuesday. The strike aimed to destroy airplanes as well as prevent take-offs and landings.
Image: 2017 Google Maps
Attack from the Mediterranean
The cruise missiles were launched from the USS Porter and USS Ross warships stationed in the Mediterranean Sea. It was the first time US forces had directly attacked government forces in the six-year civil war. Previous attacks in Syria targeted the so-called "Islamic State."
Image: picture-alliance/AP Photo/US Navy/F. Williams
Turning point for Trump
For Trump, the use of chemical weapons was a turning point in his attitude towards the Syrian conflict. After an even bigger chemical attack in August 2013, which killed several hundred people, he warned then-President Barack Obama against retaliating against Syrian President Bashar al-Assad.
Image: Reuters/C. Barria
Threats in the UN Security Council
"When the United Nations consistently fails in its duty to act collectively, there are times in the life of states that we are compelled to take our own action," US Ambassador to the United Nations Nikki Haley said on Wednesday, as she held up photographs of lifeless victims, including children.
Image: Reuters/S. Stapelton
Targeted attack or accident?
On Tuesday morning a residential district in Chan Sheikhun in Idlib province was bombed and poison gas was released. At least 70 people died in the attack, but responsibility is still unclear.
Tillerson told reporters that the "reign of the Assad family is coming to an end, and they have again brought this on themselves with their conduct" over the course of the conflict.
"Russia as their closest ally in the conflict perhaps has the best means of helping Assad recognize this reality," he said, adding that the Syrian president's departure should be done in "an orderly way."
Lavrov noted that Assad's fate "is one of the issues that Russia and the United States view differently," offering examples in which regime change failed and created further chaos in conflict-stricken countries, including Iraq and Libya.
Russia joined the Syrian conflict in September 2015, providing air support for Syrian government forces it says are fighting terrorist groups in the country. However, Moscow's involvement was largely seen as a means to bolster Assad's regime amid a protracted, multi-faceted conflict.
Asked about possible war crimes charges for Assad, Tillerson said mounting evidence that Assad's regime has engaged in war crimes could reach a threshold to bring a case against the Syrian president.
In Syria, more than 300,000 people have been killed and half the population displaced since 2011, when government forces launched a brutal crackdown against peaceful protesters calling for Assad to release political prisoners and step down.
Russia vetoes UN chemical weapons probe
Meanwhile in New York, Russia voted against a US-backed resolution to investigate a suspected chemical weapons attack in the Syrian province of Idlib.
Vladimir Safronkov, Russia's deputy ambassador to the UN, said the resolution did "not serve a useful purpose," minutes after Lavrov had called for an "independent" probe into the attack.
Matthew Rycroft, the UK's ambassador to the UN, criticized Russia's move in a statement following the vote, saying it undermined international attempts at justice.
"This is the eight time Russia has used its veto to protect the Syrian regime," Rycroft said. "Russia cannot possibly claim that it opposes the use of chemical weapons."
Earlier, the US ambassador to the UN, Nikki Haley, addressed her Russian colleagues, saying: "You are isolating yourselves from the international community every time one of Assad's planes drop another barrel bomb on civilians and every time Assad tries to starve another community to death."
Who's fighting in the Syria conflict?
Syria's civil war erupted out of the Arab Spring protests that swept much of the Middle East and North Africa in 2011. The conflict has since drawn in multiple warring factions from around the world.
Image: Atta Kenare/AFP/Getty Images
War with no end
Syria has been engulfed in a devastating civil war since 2011 after Syrian President Bashar Assad lost control over large parts of the country to multiple revolutionary groups. The conflict has since drawn in foreign powers and brought misery and death to Syrians.
Image: picture alliance/abaca/A. Al-Bushy
The dictator
Syria's army, officially known as the Syrian Arab Army (SAA), is loyal to Syrian President Bashar al-Assad and is fighting to restore the president's rule over the entire country. The SAA has been fighting alongside a number of pro-Assad militias such as the National Defense Force and has cooperated with military advisors from Russia and Iran, which back Assad.
Turkey, which is also part of the US-led coalition against IS, has actively supported rebels opposed to Assad. It has a tense relationship with its American allies over US cooperation with Kurdish fighters, who Ankara says are linked to the Kurdistan Workers' Party (PKK) fighting in Turkey. Turkey has launched multiple military offensives targeting Kurdish militias.
Image: picture-alliance/AP Photo/L. Pitarakis
The eastern guardian
The Kremlin has proven to be a powerful friend to Assad. Russian air power and ground troops officially joined the fight in September 2015 after years of supplying the Syrian army. Moscow has come under fire from the international community for the high number of civilian casualties during its airstrikes. However, Russia's intervention turned the tide in war in favor of Assad.
Image: picture-alliance/dpa/Tass/M. Metzel
The western allies
A US-led coalition of more than 50 countries, including Germany, began targeting IS and other terrorist targets with airstrikes in late 2014. The anti-IS coalition has dealt major setbacks to the militant group. The US has more than a thousand special forces in the country backing the Syrian Democratic Forces.
Image: picture alliance/AP Photo/A.Brandon
The rebels
The Free Syrian Army grew out of protests against the Assad regime that eventually turned violent. Along with other non-jihadist rebel groups, it seeks the ouster of President Assad and democratic elections. After suffering a number of defeats, many of its members defected to hardline militant groups. It garnered some support from the US and Turkey, but its strength has been greatly diminished.
Image: Reuters
The resistance
Fighting between Syrian Kurds and Islamists has become its own conflict. The US-led coalition against the "Islamic State" has backed the Syrian Democratic Forces, an alliance of Kurdish and Arab militias. The Kurdish YPG militia is the main component of the SDF. The Kurds have had a tacit understanding with Assad.
Image: Getty Images/A. Sik
The new jihadists
"Islamic State" (IS) took advantage of regional chaos to capture vast swathes of territory in Iraq and Syria in 2014. Seeking to establish its own "caliphate," IS has become infamous for its fundamentalist brand of Islam and its mass atrocities. IS is on the brink of defeat after the US and Russia led separate military campaigns against the militant group.
Image: picture alliance/AP Photo
The old jihadists
IS is not the only terrorist group that has ravaged Syria. A number of jihadist militant groups are fighting in the conflict, warring against various rebel factions and the Assad regime. One of the main jihadist factions is Hay'at Tahrir al-Sham, which controls most of Idlib province and has ties with al-Qaeda.
Image: picture-alliance/AP Photo/Nusra Front on Twitter
The Persian shadow
Iran has supported Syria, its only Arab ally, for decades. Eager to maintain its ally, Tehran has provided Damascus with strategic assistance, military training and ground troops when the conflict emerged in 2011. The Iran-backed Lebanese Shiite militant group Hezbollah also supports the Assad regime, fighting alongside Iranian forces and paramilitary groups in the country.
