(Moscow) Russia on Thursday accused the United States of having ordered the attack supposedly carried out by Ukrainian drones against the Kremlin, an attack which it says it foiled the day before. Washington denounces “a lie”.

Amid the exchange of accusations, Ukrainian President Volodymyr Zelensky demanded from The Hague, where he was on a surprise visit to the International Criminal Court (ICC), the creation of a special international tribunal to try the “crime of aggression which he says Moscow has committed against his country.

On the ground, Russian strikes have been increasing in intensity for several days, with the US State Department declaring that it has recorded 145 since May 1.

Ukraine, which claims to be completing preparations for a major offensive, said it shot down about 30 explosive drones sent by Russia on Thursday.

In the evening in Kyiv, victim of a wave of attacks the previous night, explosions were again heard by AFP journalists, the mayor of the capital, Vitali Klitschko, reporting “explosions and fires” .

However, in a clarification a few hours later, the Ukrainian Air Force admitted having had to destroy one of its own drones, a Bayraktar TB2 (Turkish-made), “during a regular flight in the Kyiv region”.

“The uncontrolled presence of the drone in the sky of the capital” would indeed “could have had undesirable consequences”, she explained, before adding that it was “probably a technical malfunction” and that no one had been injured.

But it was other drones that had previously made an impression: on Wednesday, Moscow claimed to have intercepted two of these Ukrainian devices which were targeting the Kremlin, denouncing an assassination attempt on President Vladimir Putin.

The Russian authorities have not released any evidence and it is impossible to authenticate the videos broadcast by some Russian media in which a small drone can be seen approaching the Kremlin and then exploding in a sheaf of flames.

Ukraine has in any case firmly denied any link with this affair, even accusing Russia of having “staged” it to justify a possible future escalation of the conflict, again without providing any evidence.

“The efforts of Kyiv and Washington to deny responsibility are totally ridiculous. Decisions about such attacks are not made in Kyiv, but in Washington,” Kremlin spokesman Dmitry Peskov said Thursday, without substantiating his charges.

The head of European diplomacy, Josep Borrell, meanwhile, urged Moscow not to use the Ukrainian attack “as an excuse to continue escalating” in the conflict.

The Russian capital is located some 500 kilometers from the Ukrainian border and the seat of power is in an ultra-secure district. In this context, allegations of a Ukrainian drone incursion surprised many analysts.

Russian state television on Thursday broadcast footage it said showed Mr Putin during a business meeting inside the Kremlin, his first public appearance since the alleged attack was announced.

Security measures will be “strengthened”, assured Mr. Peskov, as May 9 celebrations mark the victory over Nazi Germany in 1945 loom.

In Moscow, the large military parade planned in Red Square is maintained and Mr. Putin will give a speech there, according to his spokesperson.

Russia’s Foreign Ministry said on Thursday that “terrorist and sabotage activities of the Ukrainian Armed Forces” were taking “unprecedented scale.”

Attacks have indeed multiplied in recent days, with in particular several incursions by drones and spectacular railway sabotage.

On Thursday, drones struck two oil refineries in southwestern Russia, near Ukraine. In the evening, another was shot down near a Russian air base in Sevastopol, in annexed Crimea.

While Kyiv has not claimed any of these actions, as usual, their intensification comes at a time when Ukraine claims to have completed its preparations for a major spring offensive announced for weeks.

Rumors are rife among analysts about the date of this attack and its targets, with in any case the stated aim of reconquering the occupied territories in the East and South.

While in The Hague, home of the International Criminal Court (ICC), Mr. Zelensky called for the creation of a special court to punish the Russian “crime of aggression”, “the beginning of evil”.

He also said that Ukraine, “realistically”, did not expect to join NATO as long as the conflict continued to rage, while urging its Western allies to continue “as soon as possible” deliveries of weapons.