NATO leaders will respond to the Ukraine crisis by agreeing this week to create a "spearhead" rapid reaction force, potentially including several thousand troops, that could be sent to a hot spot in as little as two days, officials said on Monday.
The 28-nation alliance already has a rapid reaction force but U.S. President Barack Obama and other leaders meeting for a NATO summit in Wales on Thursday and Friday are expected to create a new force that would be able to respond more quickly to a crisis.
The speed with which Russian forces infiltrated Ukraine's Crimea region in March has focused minds at NATO on speeding up its ability to respond if a similar crisis ever occurred on NATO territory.
"We will develop what I would call a spearhead ... a very high-readiness force able to deploy at very short notice. This spearhead would be provided by allies in rotation, and could include several thousand troops, ready to respond where needed with air, sea and special forces support," NATO Secretary-General Anders Fogh Rasmussen told a news conference.
A senior NATO official, speaking on condition of anonymity, said the spearhead force could range from "a very small size up to something potentially as large as a brigade size". A NATO brigade typically numbers between 3,000 and 5,000 troops.
The official said the force would be able to deploy to a crisis zone in just two days. Other NATO sources said however that some elements of the force might take longer to arrive.
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Currently it takes five days for the first units of NATO's rapid reaction force to arrive.
The creation of the new force will be one of a range of measures in a "readiness action plan" that NATO will adopt at the summit to step up deterrence in response to the Ukraine crisis.
Eastern European NATO members, including Poland, have appealed to NATO to permanently station thousands of troops on its territory to deter any possible Russian attack.