Peers and MPs are set for a game of ping pong tomorrow over the government's Bill to allow four English regions to trial all-postal voting in this summer's elections.

The last day of the parliamentary term has become a deadline for the bill as ballot papers have to be printed for the June polls.

The Commons has seen its decision to approve the trials overturned four times by the Lords, who want to limit the experiment to just three regions in line with Electoral Commission recommendations.