Three polls on Saturday showed a rise in support for the opposition Labour party, although the governing Conservative party maintained a commanding lead.
The polls showed the party of British Prime Minister Theresa May remained between 11 and 17 points ahead of Labour, still enough to deliver a clear victory as she seeks a mandate ahead of negotiations over Brexit, due to begin in the summer.
However, the polls showed the gap had closed from leads of up to 25 points reported last weekend.
One poll by YouGov showed the Conservative lead over the Labour had fallen to 13 points, compared to the 23 points that the same polling firm found last week.
The YouGov poll for the Sunday Times found that 44 per cent were set to back the Conservatives, down from 48 per cent last weekend. Support for Labour climbed to 31 per cent from 25 per cent.
May said on April 11 that she would look to hold an election on June 8, to secure a mandate for her plan for leaving the European Union.
Her secure lead in the polls meant sterling rose on the prospect of an election. She has sought to portray her Conservative party as the stable option as Britain prepares to start negotiations with the EU over the terms of its departure.
A further tightening in poll ratings might generate more uncertainty over what Britain's position will be when it sits down in June to begin negotiations in earnest.
However, despite the narrowing gap, pollsters were divided over whether support for the Conservatives was actually falling.
An earlier poll by Opinium showed support for the Conservatives had actually risen two points, but the gap between the biggest parties narrowed nevertheless as Labour boosted their support by four points. Smaller parties saw their share of the vote drop.
The smallest gap between the parties was 11 points in a poll by ORB for the Sunday Telegraph. It showed support for the Conservatives at 42 per cent, while support for Labour was 31 per cent. It was ORB's first poll on the election since May called the poll last week, and is not necessarily comparable with polls by other firms.
