Edinburgh, Sep 18 (IANS/EFE): Scottish tennis player Andy Murray declared Thursday his support for the "yes" campaign for Scottish independence, saying "Let's do it!" on his Twitter account.

Murray, winner of the Wimbledon tennis tournament in 2013, had remained unbiased so far in the debate over the independence referendum held in Scotland Thursday, but shortly before the start of voting he broke his silence on Twitter.

Polling stations opened at 6 a.m. GMT Thursday in Scotland for the historic referendum on independence with opinion polls showing a virtual tie between those favouring a "yes" vote and those favouring "no".

Around 4.3 million voters over 16 years of age will decide at the polls if they believe Scotland should remain part of the United Kingdom or be an independent country.

Polling will close at 9 p.m. GMT.

The result of the vote cannot be guessed, although the latest opinion polls showed a four-point lead for the "no" vote.

"Today is a great day for Scotland!" said Murray, stressing his support for "yes" in the referendum after the negative "no" campaign waged in recent days, which warned of the economic risks of independence.

"I'm excited to see the result," noted the tennis player.

Despite his support for the "yes" vote, Murray cannot take part in the referendum as he does not reside in Scotland.

Voters resident in Scotland, including European Union citizens and members of the Commonwealth, have registered to cast their ballots in the referendum in which they are to answer "yes" or "no" to the question: "Should Scotland be an independent country?"

Last month, the player had said that if Scotland became an independent country, he would represent Scotland at sporting events.