Ukraine Conflict 'is a War,' Says Polish FM

Polish Foreign Minister Radoslaw Sikorski on Friday described the fighting in neighboring Ukraine as a "war", as the West accused Moscow of direct involvement in the escalating conflict.

"If it looks like a war, sounds like a war and kills like a war, it is a war," Sikorski wrote on Twitter about the now four-month conflict between government troops and pro-Moscow rebels.

Sikorski wrote in response to a tweet from his Swedish counterpart Carl Bildt that read: "We must call a spade a spade: this is the 2nd Russian invasion of Ukraine within a year."

Russia has repeatedly denied Western allegations that it is sending troops into eastern Ukraine, though it was forced to admit earlier this week that a number of its troops captured by Ukrainian forces had crossed the border "by accident".

On Friday, NATO chief Anders Fogh Rasmussen said that despite Moscow's "hollow denials", it was clear that Russian troops and weapons have crossed the border into Ukraine.

"We urge Russia to cease its illegal military actions, stop its support to armed separatists, and take immediate and verifiable steps towards deescalation of this grave crisis," he said.

The conflict, which has killed nearly 2,600 people according to the United Nations, has sent shivers down the spines of residents in Poland and the three Baltic states.

They have been carefully watching events unfold in Ukraine, concerned about the impact of Moscow's actions on their own security.

Baltic nations Estonia, Latvia and Lithuania spent five decades under Soviet occupation until 1991, while Poland was under Communist rule from the end of World War II until 1989.

Rasmussen said earlier this week that the Western defense alliance is preparing a rapid response to the Ukraine crisis that would allow it to deploy swiftly to reinforce eastern Europe.

U.S. President Barack Obama will meanwhile visit Estonia next week to reassure the region of Washington's commitment to its NATO allies.