He said Putin was completely open to dialogues with Trump, adding that, if necessary, a conversation between the two presidents can be arranged quickly. Trump has said he would like to have a phone talk with Putin this week.

On March 18, the two leaders conducted their second phone call this year, during which Putin agreed to Trump's proposal that Russia and Ukraine halt attacks on each other's energy infrastructure for 30 days and said he had transmitted this order to the Russian military.

But last Friday, Russian media reported that Putin wants Ukraine to set up a temporary governing mechanism to hold elections and sign agreements.

Meanwhile fighting between Russia and Ukraine continued. Russia accused Ukraine of attacking energy facilities in the Bryansk border region with drones and artillery on Sunday evening, damaging power lines and disrupting power supplies. Russia said Ukraine's actions violated its ceasefire commitments.

Ukraine accused Russia of attacking its energy facilities last week and called on the US to respond to the violation.