Russia on Thursday tightened security in Moscow as it prepares to host its annual Victory Day military parade in the capital.

Victory Day on May 9 commemorates the Soviet Union's role in defeating Nazi Germany in World War II. 

"Everything has already been strengthened in preparation for the Victory Day parade," Kremlin spokesman Dmitry Peskov told reporters.  

The celebrations associated with Russia's most important holiday take place in Moscow's Red Square. Peskov added Thursday that Russian President Vladimir Putin was working in his office in the Kremlin.

Russia on Wednesday accused Ukraine of sending drones, that were intercepted by Russian forces, in a foiled attempt to assassinate Putin.

White House national security spokesman John Kirby also denied Russian allegations that the US was behind the drone attack, calling them false. 

Senior Biden administration officials were also working to determine whether Kyiv ordered the drones that targeted the Kremlin.

Russian state news agency RIA reported Wednesday that Moscow Mayor Sergei Sobyanin issued a ban on using drones in the Russian capital unless used by authorities.

Sobyanin provided no reason for the ban, which was issued shortly before the news about the alleged drone explosions over the Kremlin broke.

Here are some of the other headlines concerning Russia's war in Ukraine on Thursday, May 4:

Zelenskyy trip leak 'unfortunate'

Ukraine's ambassador to Germany, Oleksii Makeiev, said leaked information surrounding a possible visit by President Volodymyr Zelenskyy was "very unfortunate."

"I very much hope that we will find a way out," he told Germany's DPA news agency during a visit to the border town of Frankfurt-an-der-Oder.

The possible visit was originally reported on by the Berliner Zeitung newspaper on Wednesday, citing unnamed sources. The police force responded to media inquiries the next day, inadvertently confirming the reports.

"In the morning an article appeared in a Berlin daily newspaper in which a member of the Berlin police was allegedly quoted. The press report contains confidential details of a planned operation," police said in a statement on Thursday.

International trips made by Zelenskyy, such as his visit to the Netherlands on Thursday, are usually not announced beforehand for security reasons.

Zelenskyy expects Ukraine to join NATO only after war ends

Ukrainian President Volodymyr Zelenskyy said that if his country does one day join NATO, it will be after the war.

 "We are realistic, we know that we will not be in NATO during the war," he at a press conference in The Hague on Thursday.

"But during the war, we want to get a very clear message that we will be in NATO after the war." 

Dutch Prime Minister Mark Rutte said he backed Ukraine joining the military alliance, but said it is a "very sensitive" issue due to the ongoing war.

Ukraine says downed its own drone in Kyiv after device 'lost control'

The Ukrainian air force said it downed its own drone that lost control over Kyiv, after a series of explosions shook the capital.

The explosions, which resonated for about 15 to 20 minutes in Kyiv, followed a wave of overnight Russian attacks between Wednesday and Thursday.

"At about 8:00 pm (1700 GMT) a Bayraktar TB2 unmanned aerial device lost control during a scheduled flight in the Kyiv region... the target was destroyed!" the air force said, adding it was establishing the cause of a "likely" technical malfunction.

Kyiv mayor Vitali Klitschko said "firefighters put out a fire on the ground floor of a four-storey shopping center" damaged by drone debris. The fire caused some superficial damage but no victims were reported, Klitschko said.

Russian drone downed in Kyiv causing fire on ground

An enemy drone was downed on Thursday evening, the head of President Volodymyr Zelenskyy's office said, in the fourth attack on Kyiv in as many days. Andriy Yermak gave no further details in a post on Telegram.

Meanwhile, Kyiv Mayor Vitaliy Klitschko said a fire had broken out in the Solomyanskyi district in the west of the city. He said on Telegram there could be wreckage from drone fragments and emergency crews were at the scene.

Serhiy Popko, head of the Kyiv City Military Administration also reported a drone had been downed causing a fire on the ground. There was no word on casualties or damage.

Berlin police probing leak of plans for potential Zelenskyy visit

Berlin police authorities are investigating how details about Ukrainian President Volodymyr Zelenskyy's possible visit to Berlin, typically kept under tight wraps, wound up in the press.

"In the morning an article appeared in a Berlin daily newspaper in which a member of the Berlin police was allegedly quoted. The press report contains confidential details of a planned operation," police said in a statement.

German media reported Wednesday that Zelenskyy would travel to Berlin next week before traveling on to the western German city of Aachen, where he will be awarded the 2023 Charlemagne Prize. 

The news was first reported in Berlin newspaper BZ, citing police sources, with other media outlets following suit.

Kremlin says 'absolutely ridiculous' for Kyiv to disown drone explosions

The Kremlin said it was "absolutely ridiculous" for Kyiv and Washington to try to disown the explosions over the presidential palace on Wednesday.

The Kremlin accused Kyiv of staging a drone attack in an attempt to assassinate Russian leader Vladimir Putin that was foiled by Russian forces.

Ukrainian President Volodymyr Zelenskyy said Kyiv had nothing to do with the incident.

Zelenskyy visits ICC at The Hague

Ukrainian President Volodymyr Zelenskyy visited the International Criminal Court (ICC) in The Hague on Thursday and delivered a speech about peace and justice in the war in Ukraine.

Zelenskyy called for the creation of an international tribunal to deal with "Russia's crime of aggression."

Zelenskyy's visit is a highly symbolic one — the ICC in March issued an international arrest warrant for Russian President Vladimir Putin for alleged war crimes relating to the deportation of Ukrainian children. 

Russia denies the charges and says the ICC has no jurisdiction. 

Zelenskyy was welcomed at the court by its president, judge Piotr Hofmanski. 

The trip comes off the back of Zelenskyy's visit to Finland on Wednesday where he met with leaders from Nordic countries.

Death toll rises after Russian shelling of Kherson

Local officials said the death toll of Wednesday's artillery attack on Kherson has risen to 23.

Governor Oleksandr Prokudin said the Russian shells hit a railway station, supermarket, gas station, and a home.

"The enemy's targets are the places where we live. Their targets are our lives and the lives of our children," he said.

Prokudin said 46 people had also been wounded.

President Volodymyr Zelenskyy on Wednesday decried the attacks on Kherson, condemning "the bloody trail that Russia leaves behind with its shells."

Ukraine says it destroyed 18 out of 24 Russian drones

Ukraine has down 18 out of 24 kamikaze drones that Russia launched in a pre-dawn attack on Thursday, the Ukrainian air force said.

All missiles and drones targeting Kyiv for the third time have been destroyed, said the city's administration in a statement.

"The Russians have attacked Kyiv using Shahed loitering munitions and missiles, likely the ballistic type," read the statement.

The air defense officials also added that out of 15 drones fired toward the coastal city of Odesa, 12 were destroyed while three struck a university compound.

There were no casualties, said the southern military command.

Drone attack hits Russian oil refinery

Russian emergency responders have extinguished a fire at an oil refinery on Thursday.

The fire reportedly broke out in the Black Sea port of Novorossiysk after a drone attack, setting alight tanks that contained oil products.

"A second turbulent night for our emergency services," Krasnodar governor Veniamin Kondratyev wrote on Telegram. He added that there were no casualties.

The incident comes not long after Russia reported a drone attack on the Kremlin, and days after an attack on a Russian oil depot in Crimea. Ukraine rarely claims responsibility for attacks in Russia or Crimea.

Explosions heard in Kyiv

Loud explosions could be heard in Kyiv in the early hours of Thursday morning.

"Air defenses are working in the Kyiv region," the regional military administration said on Telegram.

Local media also reported explosions in Zaporizhzhia and Odesa.

More DW coverage on Russia's war in Ukraine

The EU has big plans to step up its ammunition production to 1 million rounds per year to keep Ukraine supplied with bullets. DW explains how this will work.

German police have confirmed that Zelenskyy is set to visit the country this month — something usually kept under wraps, as was done in the Netherlands. DW looks at whether German authorities may have jeopardized this trip.

rm, zc/rc (AP, Reuters, AFP, dpa)