Barclays = all banks apparently.
MtGox had trouble with that French bank 1 year ago, that wanted to keep MtGox from opening an account with it (dont even know how that worked out). I think that Polish bank caused some disturbances as well. But so far the exchanges stayed strong. In worst case scenarios, MtGox could still move to some tax havens within Europe like Monaco, Liechtenstein, Luxemburg or the Canaries if it wants to maintain an account in the Eurozone.