Boris Johnson has secured the most support in the first round of votes in Britain's Conservative Party leadership race, while three other candidates have been eliminated.

Johnson, a former foreign secretary and leading Brexit campaigner, got 114 votes in the secret ballot among more than 300 Conservative lawmakers. Three failed to meet the threshold of 17 votes needed to stay in the race.

Seven contenders remain in the contest to succeed Theresa May as party leader and prime minister.

Further elimination votes will be held next week, with the final two contenders put to a vote of 160,000 Conservative Party members across the country. The result is expected in late July.