LONDON, May 16 (Reuters) - British Prime Minister Theresa May's Conservatives have extended their lead over the opposition Labour Party ahead of the June 8 national election as support for smaller parties wanes, a poll by Kantar Public showed on Tuesday.
The survey showed support for the Conservatives at 47 percent, up three percentage points from a similar poll last week, with Labour up one point to 29 percent.
Their gains came at the expense of the Liberal Democrats which slipped three points to 8 percent and the UK Independence Party which dropped two points to 6 percent.
"The Conservative Party look set to perform even better in the general election than in the recent local elections," said Luke Taylor, Head of Social and Political Attitudes at Kantar.
"However, it should be noted that while the Conservative Party has what appears to be an unassailable lead, other parties can still narrow the gap as more than one in 10 (12 percent) of 'likely voters' in the election are still undecided."
Kantar interviewed 1,201 people between May 11 and 15.
Another poll published earlier on Tuesday by Panelbase showed the Conservatives' lead over Labour narrowed slightly after details of Labour's policy program were published last week, but remained large at 14 points.
(Reporting by Michael Holden; Editing by William Schomberg)