Russian Deputy Foreign Minister Sergei Ryabkov said on Wednesday that preparation for a summit between President Vladimir Putin and President Donald Trump was ongoing, Russian state news agency RIA reported.

"Preparations for the summit are continuing," Ryabkov was quoted as saying. "I don't see any major obstacles."

"The question is whether the parameters outlined by the presidents in Anchorage will be fleshed out with specifics. It's a difficult process, I admit – but that’s precisely what diplomats are for."

Ryabkov was quoted by RIA as saying that he could not confirm that Russia had communicated its position to Washington in what is known as a "non-paper."

Earlier two U.S. officials and a person familiar with the situation told Reuters that Russia reiterated its previous terms for reaching a peace deal with Ukraine in a "non-paper."