Billionaire investment guru George Soros has said that it is "impossible" for Britain to reject adoption of the euro.

Mr Soros, whose currency investments have earned him a formidable reputation, warned that there were still concerns over Europe's single currency.

Harmonisation of taxes among EU states was needed to support a euro which was still "a work in progress", Mr Soros told GMTV's The Sunday Programme.

But he added that it would be "very difficult and very detrimental for Britain to be seen to be staying out".

"It's a quandary because it's dangerous to move in and particularly at what exchange rate and so on, on the other hand it's impossible to stay out," he said.

The comments came as a poll found that nearly six in 10 British MPs support adoption of the euro.

Investment record

Mr Soros' comments will be seen a particularly significant given his record as a free-thinker on the euro issue.

He two years ago warned that the euro would collapse without intervention by the European Central Bank - which followed - to support the currency.

He has also criticised the ECB over its failure to cut interest rates further to boost the eurozone economy.

Mr Soros earned the nickname "the man who broke the Bank of England" after he earned $1bn through predicting the fall of sterling shortly before its devaluation in 1992.

Politicians' views

Pressure group Britain in Europe, which supports the common currency, spent Sunday mailing 50,000 UK firms copies of a publication entitled "Staying Ahead: why British business needs the euro".

The group's campaign has been stepped up amid speculation that a referendum could be held as early as the spring of 2003.

"We are losing exports, missing opportunities and wasting �12 million a day on the administration costs of converting from sterling to the euro," Lord Marshall, Britain in Europe's chairman, said.

Levels of support in parliament for euro adoption were revealed in a poll by think tank the Social Market Foundation for ITV1's Jonathan Dimbleby programme.

The poll found that 59% of Labour backbenchers and opposition MPs supported the euro, with 39% opposing it, and 2% undecided.

But if asked how they would vote on a referendum "tomorrow", 48% of MPs said they would oppose adoption, with 46% supporting it.

The Conservative party was the most euro-sceptic of the major UK parties, with 81% of MPs opposed to adoption of the currency.

Liberal Democrats were the most euro-friendly, with only 9% of MPs opposed to scrapping sterling.