Russia and the US are preparing for a showdown at the Munich Security Conference over the controversial missile defence system the Americans want to build in Europe.
US Secretary of State Hilary Clinton is a keynote speaker at the annual event, which brings together important international security figures, and Russian security officials will also be present.
The defence system is expected to be high on the agenda.
Dmitry Medvedev, Russia's president, raised tensions between the two countries in November when he said Russia would "destroy" parts of the proposed defence system.
"I have given the armed forces the task of drawing up plans to destroy the information and command and control systems of the anti-missile shield," Medvedev said.
"Our NATO partners are not for now showing any readiness to take our concerns about the architecture of the European missile shield into account, something which convinces us that their plans are aimed at Russia."
American security officials said their plans do not interfere with Russia's security.
"In multiple channels, we have explained to Russian officials that the missile-defence systems planned for deployment in Europe do not and cannot threaten Russia's strategic deterrent," Tommy Vietor, spokesman for the US National Security Council, said.
The American government insists the network would be for defence against long range ballistic missiles from countries like Iran and North Korea.
There was a war of words between the two superpowers back in 2009 when the US looked as though it would be deploying missile defences in Poland and the Czech Republic - something Russia said the US could use for spying.
"We will not be hysterical about this, but we will think of retaliatory steps," Dmitry Medvedev, Russia's president, said at the time.
In September 2009 President Barrack Obama withdrew plans for a missile defence system in Poland and the Czech Republic after Russia's opposition and an internal American review recommending the deployment of US warships in the Black Sea instead.
Plans still exist for a US/NATO defence system elsewhere across Europe.