Donald Trump and Vladimir Putin held a critical phone call on Tuesday, speaking for at least an hour and a half on a Ukraine ceasefire plan that could involve forcing Kyiv to cede swathes of territory to Russia.

The US president has already made clear he wants to discuss what parts of occupied Ukraine that Russia will be allowed to keep, saying at the weekend Moscow and Washington are talking about "dividing up certain assets." 

The call came amid concerns in Kyiv and European capitals that the 78-year-old Trump will give too much ground to the Russian president, a leader for whom he has repeatedly expressed admiration.

Putin's spokesman Dmitry Peskov said that "the conversation has come to an end," according to the state TASS news agency. The White House confirmed the end of the call and said it would issue a statement soon.

The talks were clearly lengthy, with Trump's deputy chief of staff Dan Scavino saying the call began at 1400 GMT and was "going well." About 90 minutes after the call started, Scavino said it was still in progress.

A ceasefire is still far from guaranteed, however.

Kyiv has agreed to halt fighting for 30 days and enter talks with Russia more than three years into Moscow's invasion, but Putin has set a string of conditions including that Ukraine be barred from joining NATO.

Trump said on his Truth Social network late Monday that "many elements of a final agreement have been agreed to, but much remains" to be settled.

Putin speech

Putin gave a hardline anti-Western speech Tuesday before the call, saying the West would still try to undermine Russia even if it lifted sanctions imposed over its invasion of Ukraine.

He mocked the G7 group of rich democracies -- from which Russia was expelled in 2018 -- to wild applause from the audience, saying it was too small to "see on a map."

Kyiv said it expected Moscow to "unconditionally" accept to the ceasefire.

"It is time for Russia to show whether it really wants peace," Ukraine's Foreign Minister Andriy Sybiga said.

Ukrainian President Volodymyr Zelensky has warned Putin does not want peace and is trying to achieve a better position militarily ahead of any halt in fighting.  

Russia has attacked Ukraine with near daily barrages of drones and missiles for more than three years, occupying some 20 percent southern and eastern Ukraine and pressing a grinding advance in recent months.

Putin has said that a ceasefire only benefits Kyiv and not the Russian army, that he said was "advancing". 

Moscow has also said that will not accept Western troops deployed as peacekeeping forces in Ukraine and has said it was against the US arming Ukraine during any halt in fighting.

The push towards a ceasefire began in February when Trump announced last month that he had spoken to Putin -- a surprise call that broke Western efforts to isolate the Russian leader while his invasion continues.

As Trump upended years of US policy he then had a televised shouting match with Zelensky in the Oval Office on February 28, which led to the United States temporarily suspending its billions of dollars in military aid to Kyiv.