Discussions are underway for a potential meeting between US President Donald Trump and Russian President Vladimir Putin ahead of the G20 summit in July, a Kremlin spokesman said.

The two leaders have never met, but have spoken warmly of one another and have pledged to renew US-Russian relations.

Kremlin spokesman Dmitry Peskov told reporters on 13 February that a possible meeting of the leaders ahead of the G20 summit in Germany had been discussed, but nothing had been decided on.

The Trump administration has come under intense scrutiny for ties between key officials and the Kremlin, with US intelligence agencies claiming that Russia interfered in the election in an effort to help secure Trump's election.

There have been calls for US national security director Michael Flynn to be sacked, after reports that he had spoken with Russia's US ambassador Sergei Kislyak about relaxing sanctions ahead of Trump's election, a possible contravention of US law. Peskov denied there had been any discussions on sanctions between Russian and US representatives.

On Friday, Putin said that Slovenia would be a good place for a potential meeting, but that the choice of venue would not be Moscow's alone. Slovenia is the birthplace of Trump's wife, Melania.

The G20 summit of the world's most powerful economies is scheduled to take place in Hamburg, Germany, on July 7 and 8.