Britain's ruling Labour party has cut the opposition Conservative party's lead to just four points ahead of an election expected to be held on May 6 and could remain the largest party in parliament, Reuters cited a poll as showning. An ICM poll for Tuesday's Guardian newspaper put the Conservatives on 37 percent of the vote, Labour on 33 percent, and the smaller opposition Liberal Democrats on 21 percent. It said the gap between the two main parties was the narrowest in an ICM poll for almost two years. If the projections were repeated uniformly across the country, Labour would be the largest party in a 650-seat parliament but would be 30 seats short of an overall majority, the paper said on its website.