US President Donald Trump and Russian President Vladimir Putin will travel to Friday's summit in the US state of Alaska with contrasting priorities as they prepare for talks on ending Russia's war in Ukraine.

Putin has been consistent on his desire to win Ukrainian territory, while Trump has made no secret of his desire to act as a global peacemaker.

But both men may also sense other opportunities, such as diplomatic rehabilitation on the world stage on the part of Putin. Second-guessing Trump's aims is harder, as he has recently made vacillating statements about his Russian counterpart.

Here's a fuller look at what the two leaders might want from the meeting.