Speaking in the Commons, Ed Balls has just made the remarkable declaration that "there's no possibility anytime in my lifetime of a British government joining the euro". His statement represents a significant shift of policy by Labour, which had previously said only that it was unlikely that Britain would join the single currency in the near future. In his recent speech  on the EU, Douglas Alexander, the shadow foreign secretary, said that while joining the euro "is not on Labour's agenda" there "is no need to be dogmatic on these questions", noting that "future generations of politicians may find that circumstances have changed".
But Balls, who is deservedly proud of his role in keeping the UK out of the euro, felt that an unambiguous statement was needed. Labour's policy reversal leaves the Lib Dems as the only one of the three main parties refusing to rule out euro membership.
Incidentally, for a list of prominent political figures who still support UK membership in theory, see my blog from last month, "Who still thinks Britain should join the euro? "