Britain's Prime Minister Theresa May speaks at a campaign event in North Tyneside, Britain. May 12, 2017. REUTERS/Scott Heppell

LONDON (Reuters) - British Prime Minister Theresa May’s Conservatives have slightly extended their large lead over the opposition Labour Party as the state-run health service takes over from Brexit as the nation’s top concern, a poll said on Monday.

The Conservatives were on 48 percent, up one point from a similar survey a week before, with Labour unchanged on 30 percent, the Survation poll for the Good Morning Britain TV show found.

The Liberal Democrats were on 8 percent, up one point, with the UK Independence Party unchanged on 4 percent.

The poll of 1,016 people, carried out on May 12-13, found the National Health Service was now the most important issue for voters overtaking Brexit, followed by the economy, immigration and education.