The government could soon extend tax relief for films to some television dramas to discourage producers from filming overseas, a Treasury source said on Friday.

The government will launch a consultation in next week's budget to examine the benefits of a 20-25 percent cut in corporation tax for the makers of shows which appeal to export markets such as period drama Downton Abbey.

One of the ways the world sees Britain at its best is through world-class films and television made in Britain, the Treasury source said.

They not only help us showcase the country, but are also an important part of a dynamic and diversified economy. Tax relief for British films has been critical in ensuring that industry continues to thrive.

The offer of tax relief would depend on a series of tests to ensure any drama series was culturally British and of high quality.

The move would bring Britain in to line with many other countries that offer tax relief to the television production industry, such as France, Hungary, Ireland and South Africa.

British Prime Minister David Cameron and his chancellor, George Osborne, are on a visit to the United States where Downton Abbey, a country house drama set in the early 20th century went down well in the United States.

It was made in Britain but many other British-led productions - such as Titanic and The Tudors - are either filmed or produced abroad because of more friendly tax regimes.

UK officials hope the tax measure will keep high-end drama production in Britain and boost a creative sector which has total annual revenues of more than 2 billion pounds.

Time and time again, great British programmes are being made overseas where the tax climate is more favourable, said Julian Fellowes, writer of the Downton Abbey and Titanic series. If the budget can address this it would be a fantastic move forward for our industry.

Economists estimate that Britain's film industry would be about 75 percent smaller without its dedicated tax credit.

(Reporting by Matt Falloon; Editing by Robin Pomeroy)