Six years of conflict have brought the Syrian health service, once one of the best in the Middle East, close to collapse. Fewer than half of the country's hospitals are fully functioning. Around 200 children visit the Children's Hospital in Damascus every week, with more than 70 percent from outside the capital.

Young cancer patients wait for treatment at Damascus Children's Hospital. Local and World Health Organization officials blame Western sanctions for severely restricting pharmaceutical imports, even though medical supplies are largely exempt from measures imposed by the United States and European Union.

Cuts in health expenditure by the Syrian government fighting a hugely expensive war, a drastic fall in the value of the currency and indirect effects of the sanctions are all deepening the misery of patients who need foreign-made drugs. Before the conflict, Syria produced 90 percent of the medicines it needed but anti-cancer drugs were among those where it traditionally relied on imports.

Nurses taking care of a sick child. The World Health Organization in Syria, says medicine imports have been hit by significant cuts in the government's health budget since the war began in 2011. Adding up tot hat is a 90 percent drop in the value of the Syrian pound, which has made some pharmaceuticals prohibitively expensive.

"The impact of economic sanctions imposed on Syria heavily affected the procurement of some specific medicine including anti-cancer medicines," says Elizabeth Hoff, the WHO representative in Syria. "The sanctions were preventing many international pharmaceutical companies from dealing with the Syrian authorities as well as hindering foreign banks in handling payments for imported drugs."

Cancer patient Fahd plays with his mobile phone while his mother sits by his bed. Both the U.S. and EU sanctions include exemptions for medicines and other humanitarian supplies. However, by clamping down on financial transactions and barring much business with the Syrian government, the sanctions are indirectly affecting trade in pharmaceuticals.

One private charity, Basma, is trying to help out by funding cancer drugs for poor families. The proportion of patients who need assistance has risen from about 30 percent to nearly 80 percent since the war began, according to executive manager Rima Salem. Salem finds the delays in treatment worrying. "A child with cancer might die waiting for his turn to get treatment," she said.

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.

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.

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."

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.

"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.

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.