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LONDON, June 17 (Reuters) - Britain's Times newspaper has come out in support of remaining in the European Union, an emailed copy of the front page of its Saturday edition showed, setting up an unusual political face-off with another newspaper in media tycoon Rupert Murdoch's stable.

The Times front page showed a leading article entitled "Why Remain is best for Britain".

"On balance we believe Britain would be better off leading a renewed drive for reform within the EU rather than starting afresh outside it," the newspaper said.

The position of the Times is contrary to that of the Sun, which is also owned by Murdoch. This week the Sun, the UK's biggest-selling paper, declared it was for leaving the European Union.

"The Sun urges everyone to vote Leave. We must set ourselves free from dictatorial Brussels," the tabloid said.

The Sun has a circulation of 1.7 million compared with some 437,000 readers for The Times. Both newspapers backed the Conservative Party in the 2015 general election, but the EU referendum has opened up divisions that cut across parties.

The Times cited concerns over immigration, a key rallying point of the "Leave" camp. It said the referendum "has rightly been a thunderous rebuke to Europe."

British newspapers have historically claimed to hold some sway over the electorate, most famously the Sun in 1992. After the election of John Major's Conservative party it ran the headline, "It's the Sun Wot Won It."

The Times position came a day after British lawmaker Jo Cox was murdered. Campaigning by the Leave and Remain camps for the June 23 referendum has been suspended as a sign of respect. (Reporting By Freya Berry; Editing by Hugh Lawson, Toni Reinhold)

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