The US Secretary of Defense James Mattis said on Thursday that he did not see a possible military collaboration with Russia in the time being, in a blow to Moscow's hopes to mend ties with Washington after Trump's election.
The remarks came despite repeated suggestions by US President Donald Trump during his election campaign of the possibility of joint action against the Daesh terror group.
"We are not in a position right now to collaborate on a military level. But our political leaders will engage and try to find common ground," said Mattis after talks at NATO headquarters in Brussels.
He also mentioned US concerns about Russian interference in democratic elections.
"Right now, I would just say there's very little doubt that they have either interfered or they have attempted to interfere in a number of elections in the democracies," Mattis said. He did not explicitly cite the US election.
Just hours before Mattis spoke, Russian President Vladimir Putin said it was in the interests of both nations to restore communications between their intelligence agencies.
Meanwhile, the US Secretary of State Rex Tillerson and Russian Foreign Minister Sergei Lavrov held talks on the sidelines of the G20 summit in Bonn, to discuss Ukraine among other issues.
Rex Tillerson said the US is ready to cooperate with Russia but that there are some disagreements.
It's the first time the two men have spoken since Donald Trump became US President.