European leaders will visit the United States on Monday or Tuesday to discuss ways to end the war in Ukraine, Donald Trump has said.

The US president added that he would also speak to Russian President Vladimir Putin “soon”, as well as signalling that his administration was ready to move to a second phase of sanctions on Moscow.

Ukrainian President Volodymyr Zelensky said the sanctions were the “right idea”, and urged European nations to stop buying Russian energy.

It comes as Russia launched its largest aerial bombardment on Ukraine of the war so far, killing four and hitting Ukraine’s main government building in Kyiv for the first time.

After the attack, during which Russia fired at least 810 drones and 13 missiles at Ukraine, Trump said he was “not happy with the whole situation”.

“Certain European leaders are coming over to our country on Monday or Tuesday individually,” Trump said. It was not clear to whom Trump was referring.

Russia has intensified attacks on Ukraine since Trump and Putin held a summit in Alaska last month.

Speaking to ABC News, Zelensky said that European partners continuing to buy Russian oil and gas was “not fair”.

He added: “We have to stop [buying] any kind of energy from Russia, and by the way, anything, any deals with Russia. We can’t have any deals if we want to stop them.”

Zelensky also welcomed Trump’s plans to impose secondary tariffs on countries that trade with Russia – aimed at frustrating Moscow’s ability to fund the war.

“I think the idea to put tariffs on the countries who continue to make deals with Russia, I think this is the right idea,” he said.

Russia has sold around $985bn (£729bn) of oil and gas since its full-scale invasion of Ukraine began in March 2022, according to the think tank the Centre for Research on Energy and Clean Air.

The biggest purchasers have been China and India. The EU has dramatically reduced – but not completely stopped – purchases of Russian energy. In June, Brussels laid out plans to end all purchases by 2027.

Last month, the US imposed tariffs of 50% on goods from India as punishment for continuing to buy Russian oil. The Indian government has said it will continue to pursue the “best deal” on buying oil for the economic interests of its population.

And at a meeting in Beijing last week, Russia said it would increase supplies of gas to China.

Zelensky’s intervention comes as the OPEC+ group of oil producing nations, which includes Russia, has again agreed to increase production, a move which will put downward pressure on oil prices.

US Treasury Secretary Scott Bessent told NBC’s Meet the Press that the US was looking for more support from the EU to impose secondary tariffs on countries that buy Russian oil.

Bessent said that if EU nations increased sanctions and secondary tariffs on countries that buy Russian oil, “the Russian economy will be in total collapse, and that will bring President Putin to the table”.

He added: “We are in a race now between how long can the Ukrainian military hold up, versus how long can the Russian economy hold up.”