File photo of Russian President Vladimir Putin
British Defence Secretary Michael Fallon said Russian President Vladimir Putin poses a "real and present danger" to Estonia, Latvia and Lithuania on Thursday and said NATO is getting ready to repel any possible aggression.
Mr Fallon, whose remarks were published as Britain said it had scrambled jets to see off Russian Bear bombers, said Putin could launch a campaign of undercover tactics to try to destabilise the three former Soviet republics, now on NATO's eastern flank.
"I'm worried about Putin," Fallon told the Times and Daily Telegraph newspapers, saying there was "a very real and present danger" Russia would seek to replicate the tactics it used to unsettle eastern Ukraine and Crimea in the Baltics.
"I'm worried about his pressure on the Baltics, the way he is testing NATO. NATO has to be ready for any kind of aggression from Russia whatever form it takes. NATO is getting ready," he said.
Mr Fallon's intervention came as Ukrainian President Petro Poroshenko called for U.N. peacekeepers to monitor a ceasefire in eastern Ukraine, a proposal pro-Russia rebels said would breach a peace deal.
Mr Fallon also raised concerns about increased Russian air activity around Britain as his ministry announced the Royal Air Force had escorted two Russian long-range Bear bombers away from the south coast of England the previous day, the second such incident in as many months.
Mr Fallon earlier this month said Britain would send four Typhoon fighter jets again this year to help NATO with air policing in the Baltic states, promising up to 1,000 British troops would also join a NATO rapid reaction force.
Lithuanian Foreign Minister Linas Linkevicius said Russia posed a threat to the wider region, including Moldova, which on Wednesday chose a pro-European businessman as prime minister.
"Russia is behaving aggressively now as we speak," he told BBC radio.
"I really do see threats to all countries ... I shouldn't say just to the Baltic states but also with regard to others."
NATO would react to any threat to his country's territorial integrity, he said.
"If we fail to react properly to what's happening in Ukraine, there will be a big temptation (for Russia) to further instigate situations elsewhere and then we will face a bigger problem," Linkevicius said.
Britain's relations with Russia have deteriorated since the start of the Ukraine crisis. London has become one of Putin's fiercest critics, regularly arguing that European Union sanctions on Moscow must be maintained and possibly expanded.
© Thomson Reuters 2015