The taxman is making his first appearance on YouTube today in an attempt to increase pressure on savers who have not declared their offshore accounts.

Dave Hartnett, HM Revenue & Customs’ Permanent Secretary for Tax, appears in a hard-hitting two-minute video warning that people “fiddling” their taxes could face jail.

It is the first time that HMRC has used social media to communicate with the public. Previously it has run television campaigns to encourage people to file their tax returns on time and to collect their tax credits.

A spokesman said: “We are looking to use social media, alongside more traditional communications to reach as wide an audience as possible. YouTube is clearly a popular platform for brief, to-the-point communications and that is why we have decided to post the video there.”

Mr Hartnett, who masterminded this crackdown on offshore savers, said that his message was “blunt”. “For some people, offshore bank accounts and tax havens typically conjure up images of exotic and faraway places, well out of the reach of the taxman at home,” he said.

“Well, life’s just not like that any more. And here’s a blunt message from HM Revenue and Customs: times have changed. The taxman now has more powers and more information ... If you evade tax on your offshore assets, you’ll be found out and you could be prosecuted.”

He urged savers to take advantage of HMRC’s tax amnesty launched in July this year, which limits the penalties for those who come forward to notify the Revenue before November 30 that they have offshore interests.

Under the terms of the New Disclosure Opportunity (NDO), those who declare that they have savings or other income from overseas, for example from renting out property, will pay all the tax they owe plus a 10 per cent penalty.

Savers who notify HMRC by phone or in writing must pay the tax and penalty by January 31. Those who alert the Revenue online have until March next year to settle their bill. Those who fail to come forward face penalties of up to 100 per cent of the tax they owe and could face prosecution.

This is the second such amnesty that has been offered by the taxman, but HMRC says that it will be the last.

The initial disclosure regime, which closed in 2007, raised £400 million for the Treasury coffers after 45,000 savers came forward.

At that time, HMRC had obtained details of all Britons holding money offshore from five leading banks. Since then HMRC has collected information on thousands more British savers from hundreds of smaller banks. Accountants say that the taxman could have details of as many as 100,000 people. HMRC would not reveal how many people had come forward under the NDO, but it said that it expected a flood of disclosures ahead of the November deadline.

A spokesman said: “We do not expect to have a full picture of the amount of tax, interest and penalties recovered until the deadline for payment has passed in March 2010.”

Appealing to savers’ consciences, the video points out that “by fiddling your tax, you’re robbing public services of much-needed funding”. In a line reminiscent of a gangster movie, Mr Hartnett adds that the possibility of jail for those who do not declare their income “is not a hollow threat”.

Accountants say that HMRC has become more hardline about chasing tax payments as the income from tax has dwindled during the recession. Angela Beech, tax partner at Blick Rothenberg, the accountant, said: “The Revenue are getting more threatening as they have a huge black hole to fill because of plummeting tax receipts.”

In May it emerged that HMRC would use debt collectors to chase individuals and businesses who have failed to settle their tax bills.

See the video at timesonline.co.uk/business

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