US President Donald Trump said his meeting with Russian leader Vladimir Putin in Alaska could fail, but it's just a prelude to a second, three-way meeting where the real deal on the war in Ukraine will be made.

Trump and his Russian counterpart will hold talks aimed at resolving the conflict in Ukraine during their historic summit at a US air base near Anchorage on August 15.

Ukrainian President Volodymyr Zelensky will not attend this meeting, but Trump hinted that there could be a second meeting with both leaders if the first one is successful, AFP reported.

"This meeting is preparing for the second meeting. The second meeting will be very, very important because they will make a deal. And I don't want to use the word 'separation'. But you know, to a certain extent, it's not a bad term, is it?" he told Fox News Radio.

Russia's intensified offensive and Zelensky's exclusion from the Alaska meeting have heightened fears in Europe that Trump and Putin could strike a deal that would impose painful concessions on Ukraine.

The US president initially said there would be a "land swap," but he appears to have backed away from that position after talks with European leaders on August 13.

However, his comments today suggest that he has not completely ruled out the possibility of a land swap.

Trump said that "there is a 25% chance that this meeting will not be successful." | BGNES