Ukrainian negotiators are holding talks in the United States on Sunday to discuss Washington's plan to end the war with Russia, as Kyiv faces political and military pressure.

As Russia advanced along the front line, its forces targeted the Ukrainian capital and its surrounding region for two consecutive nights ahead of talks in the United States.

An attack on a rally on the outskirts of Kyiv left one person dead and 11 injured on Saturday night, according to the regional governor.

Hours earlier, a Ukrainian security source announced that Kyiv was responsible for attacks targeting two oil tankers in the Black Sea suspected of secretly transporting sanctioned Russian oil.

The talks in the United States come amid political turmoil facing Ukrainian President Volodymyr Zelensky and his government, as a corruption investigation forced him to fire his chief of staff and chief negotiator, Andriy Yermak, on Friday.

The Ukrainian delegation, led by Rustam Umarov, is scheduled to meet with U.S. Secretary of State Marco Rubio and Washington's special envoy, Steve Witkoff, in Florida on Sunday, according to a U.S. official.

Washington has presented a plan to end the conflict that began more than three years ago and is seeking to finalize it with the approval of Moscow and Kyiv.

The first version of the 28-point proposal, which was drafted without any input from Ukraine’s European allies, stipulated the withdrawal of Ukrainian forces from the Donetsk region (east) and de facto US recognition of the Donetsk, Crimea and Luhansk regions as Russian.

The United States amended the original draft after criticism from Kyiv and Europe, but the current version is still unclear.

The French presidency announced that President Emmanuel Macron will hold talks with Zelensky in Paris on Monday.

Targeting a Russian oil facility

Hours before the Ukrainian delegation was due to leave, operations at one of Russia’s largest oil ports were halted on Saturday following an attack by drone boats.

The Caspian Pipeline Consortium, which includes the two major US oil companies ExxonMobil and Chevron and owns the facility, described the strike as a “terrorist attack.”

Ukraine has not commented on the incident, although it has repeatedly targeted Russian energy facilities in the hope of draining Moscow's war coffers.

The Caspian Pipeline Consortium pipeline, which starts in Kazakhstan and ends at the port, is primarily intended for transporting oil from Kazakhstan and is among the largest in the world, handling about one percent of global oil supplies.

But a Ukrainian source claimed responsibility for an attack on two oil tankers in the Black Sea suspected of being part of the Russian stealth fleet used by Moscow to circumvent Western sanctions.

Explosions rocked the two tankers, Firat and Kairos, which were empty off the Turkish coast on Friday, according to the Turkish Ministry of Transport.

The ministry stated that one of them was targeted again on Saturday morning.

A source in the Ukrainian Security Service told AFP that Sea Baby-type maritime drones"successfully targeted the two vessels."

The source shared a video recording that, according to him, shows the naval drones heading towards the two ships, causing the explosions.

Drone attacks

For its part, Russia continued its nighttime attacks on its neighbor.

Kyiv region governor Mykola Kalashnyk reported another"enemy drone attack" in the early hours of Sunday morning.

He said on Telegram: “Unfortunately, as a result of the enemy attack on Vyshgorod, one person was killed and 11 others were injured, including a child.”

This attack followed another Russian attack on Friday evening with drones and missiles, which killed three people and cut power to hundreds of thousands across Ukraine.

Russia, which denies targeting civilians, announced that it had struck energy infrastructure that powers Ukraine's military-industrial complex.

But Ukraine suggests that the Russian attacks are aimed at exhausting its civilians.

Following violent explosions on Saturday night, Ukrainian media worker Galina Bondarenko told AFP in Kyiv that shrapnel had fallen into her home.

She said: “One of the fragments fell near the bed. It hit the bed and then got stuck.”