Kremlin has said ahead of the Alaska summit on Ukraine that a subsequent three-way meeting would be possible if talks between Vladimir Putin and Donald Trump bear results, according to Russia's Interfax news agency.

Spokesperson Dmitry Peskov said on Friday that the talks between Russian and US presidents may last 6-7 hours, and their aides will take part in meetings that were expected to be held one-to-one, Russian state media reported.

Russian special envoy Kirill Dmitriev also said ahead of the meeting that the mood is "combative", Russia's RIA news agency reported.

Putin and Trump will discuss the full spectrum of US-Russia relations, not only Ukraine, and their talks will be aimed at restoring ties, said Dmitriev, who is responsible for investments and economic cooperation.

The high-stakes meeting at Joint Base Elmendorf-Richardson in Anchorage will also mark the first direct talks between sitting US and Russian presidents since June 2021, when then-President Joe Biden met Putin in Geneva.