At least 7,000 reservists have been recalled to the colours for immediate exercises lasting between 10 and 30 days.
They're told by the Polish authorities that the call-ups are “routine”: but the men say they haven’t been asked before and they’re well aware of the growing alarm in Warsaw at President Putin’s aggression.
http://www.theweek.co.uk/europe/ukraine/57830/why-are-polish-men-london-getting-military-call-papers
Nato to bolster defences of Baltic states amid Ukraine crisis
Cameron says British army will help beef up defences in Lithuania, Estonia and Latvia to deter possible Russian aggression
http://www.theguardian.com/world/2014/mar/24/cameron-nato-baltics-states-defences-ukraine-crisis