The U.K.'s governing Conservative Party held a lead of only 3 percentage points over the opposition Labour Party in a YouGov poll published June 1 ahead of the June 8 election, although the gap was as much as 12 percentage points in another poll taken only two days earlier.

The Conservatives had 42% in the poll, ahead of Labour's 39% and the Liberal Democrats' 7%. The United Kingdom Independence Party trailed with 4%, and the Greens had 2%.