Britain is going to the polls on Thursday, after Prime Minister Theresa May announced an early general election in April. 

About 46.9 million people have registered to vote at more than 40,000 polling stations across the country, after polls open at 7:00 a.m. local time. The vote is expected to last until 10:00 p.m. local time, and counting will start afterwards.

Opinion polls showed on the eve of the election that May will boost a majority in parliament, but the Labor Party, led by Jeremy Corbyn, has been narrowing sharply since she announced the snap election.

Britain's Prime Minister Theresa May waves to supporters during a general election campaign rally in Birmingham. /VCG Photo

However, the polls suggested that May's gamble to call the vote to bolster her position in Brexit negotiations will pay off.

Of the six polls published on Wednesday, two showed the Conservatives widening their lead over Labor, two showed a narrowing, and two were unchanged.

But they mostly suggested she would increase the small majority she inherited from David Cameron last year, shortly after the surprise referendum decision to take Britain out of the European Union.

Polling firm ICM said the Conservatives' wide lead of 46 percent to 34 percent for Labor would give May a majority of 96 seats, up sharply from the working majority of 17 she has had until now and bigger than any Conservative majority since the days when Margaret Thatcher was the prime minister.

Jeremy Corbyn, leader of the Labor Party arrives on the Labor battle bus to speak at a campaign rally at Union Chapel Islington. /VCG Photo 

The Independent newspaper said the 44-34 lead for the Conservatives in a poll it commissioned from ComRes would give May a majority of 74.

YouGov, which found the Conservatives' lead had increased to seven percentage points from four during the weekend, also said May would bolster her power in the parliament.

"The seven-point Conservative lead is the same as at the previous election, but we think it is likely they will nevertheless be returned with an increased majority," YouGov Director Anthony Wells said.

The polls were conducted after a deadly attack by Islamist militants in London on Saturday.

Supporters of Britain's opposition Labo‍r Party leader Jeremy Corbyn hold signs during a general election campaign rally in Watford. /VCG Photo

ICM and ComRes have tended to give the Conservatives bigger leads than other polling firms.

At the other end of spectrum, Survation said the Conservatives' lead stood at just one percentage point, echoing two polls it published in recent days which called into question whether May would get a majority at all.

Polling experts have said the main difference between the polls which give the Conservatives a big lead and ones such as Survation which suggest a tighter race is largely down to varying estimates of how many young voters, who typically support Labor, are likely to actually vote on Thursday.

Investors took the latest findings as a sign May was likely to emerge victorious, giving her a boost before the start of Brexit talks this month. Sterling rose by nearly half a cent against the US dollar after the ICM poll was published.

(Source: Reuters)