With a week to go until election day, the leaders of Britain's three main political parties are making their last big televised bid to win over undecided voters.

Conservative leader David Cameron, Labour's Ed Miliband and Liberal Democrat chief Nick Clegg are fielding questions from voters at Leeds Town Hall in northern England — though they won't debate one another.

Cameron, the prime minister, went first Thursday, defending his government's cuts to welfare benefits and arguing that his "difficult decisions" had curbed the deficit and restored Britain's economy.

Debates have been a cause of election friction. Cameron's opponents branded him "chicken" after he agreed to participate in only one, a seven-way faceoff on April 2. Opposition leaders later held another debate without him.

Britons go to the polls May 7.