Ushakov said he met with U.S. National Security Advisor John Bolton.
Putin also hoped that meeting with Trump to be held when American side is ready.
Trump's administration has accused Russian Federation of non-compliance with the 31-year-old Intermediate-Range Nuclear Forces (INF) treaty and has said it will pull out of the deal as a result.
"I think we're very close to doing something with China, but I don't know that I want to do it", Trump told reporters.
Kiev and Moscow continue to trade barbs, amid accusations of a large-scale Russian invasion of Ukraine.
Trump had cancelled a scheduled bilateral meeting with Putin in Argentina, but White House spokeswoman Sarah Sanders said the two did have an "informal" conversation when they crossed paths at a summit dinner Friday.
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Merkel said she had also discussed Syria with Putin, "especially in the Idlib region", where a fragile ceasefire has been negotiated between rebels and Syrian army forces backed by Moscow.
European Council President Donald Tusk was more focused on the Ukraine crisis, saying he was "sure" the bloc would roll over its sanctions on Russian Federation next month.
The Ukrainians reject Russian insistence that they use a Russian pilot, saying it is not required by a 2003 agreement on sharing the waterway, and is a recently imposed means of controlling Ukrainian access. "I answered his questions", Putin said, according to Bloomberg.
"Should there be any other aspirations, such as taking advantage of the trade spat to throttle Chinese growth, then an agreement is unlikely to be reached", the newspaper said in an editorial Friday. The US Senate unanimously accused Moscow of aggression.
As for Macron, "the main message that he passed on is really that of a de-escalation", the aide said.
But Trump is also under mounting pressure at home in an investigation over whether his presidential campaign colluded with Russian Federation - a topic sure to dominate his press conference shortly before he meets Xi over dinner.
In the confrontation on November 25, Russian vessels first rammed a Ukrainian navy tugboat and later opened fire before boarding three naval boats and taking all 24 crewmembers into custody, including six who were wounded - three apparently seriously.
"The current Ukrainian leadership is not interested in resolving this at all", Putin said.