Nationwide support for the United Kingdom Independence Party has surged to 25 percent after the anti-EU party won its first seat in parliament, according to a shock survey published on Sunday.

UKIP, opposed to mass immigration as well as Britain's membership of the European Union, could win enough seats to hold the balance of power with such a level of support, an expert said.

The Survation poll in The Mail on Sunday newspaper put Prime Minister David Cameron's Conservatives and the Labour opposition neck-and-neck on 31 percent.

The Liberal Democrats, the junior partners in the governing coalition, were on eight percent. Survation interviewed 1,003 people online on Friday.

An Opinium poll in The Observer newspaper put Labour at 35 percent, the Conservatives at 28, UKIP at 17 and the Liberal Democrats at nine.

Some Conservative MPs have called for a pact with UKIP in seats where the anti-Brussels party might have a better chance of beating Labour, claiming the alternative was "mutually-assured destruction" through a split vote.

But UKIP leader Nigel Farage said on Saturday he would not enter into a pact with the Conservatives ahead of the May 2015 general election, insisting they were "not a splinter" of the Tories.

UKIP were voted into parliament for the first time in a by-election on Thursday when Douglas Carswell, who defected from the Conservatives, retained his coastal Clacton seat in eastern England.

A second Conservative MP, Mark Reckless, has also defected and will fight a by-election, while Carswell told The Sunday Times newspaper that he had spoken to a Labour MP who was considering the switch.

John Curtice, professor of politics at Strathclyde University and an electoral behavior expert, said that if the Survation poll ratings were translated into general election results, Labour could win 253 of the 650 seats in parliament, the Conservatives 187, UKIP 128, the Liberal Democrats 11, and other parties such as the Scottish nationalists 71.

(China Daily 10/13/2014 page11)