LIBERAL Democrat leader Vince Cable has defended the controversial privatisation of Royal Mail that he presided over during his time as Business Secretary.

Cable said the sell-off was a "successful episode" of the five years of Tory-Lib Dem coalition government at Westminster from 2010 to 2015.

Speaking to the Sunday Herald, Cable said the move had revived the service and allowed it to raise funds for investment.

He also denied the taxpayer has lost out by £1billion because of the privatisation, which critics say was sold off too cheaply.

However, Labour MP Hugh Gaffney, a former postman, said the policy had been a "disaster" by leaving customers and employees worse off.

Cable, who was elected unopposed as Lib Dem leader last month, defended the policy during a visit to Edinburgh, where he met supporters.

Cable said of the privatisation: "That caused some controversy, but actually it was a successful episode. It was the only way to raise capital for the Royal Mail to expand because it was a dying business and we know why it was dying because of email.

"Every time someone sent an email it was taking business from the Royal Mail so they had to change their business to make it a logistics company and to do that they had to raise lot of capital. It's been a success so I don't see that as being in anyway a negative."

Westminster Business, Innovation and Skills Select Committee previously said that taxpayers may have lost out on about £1bn from the undervaluing of Royal Mail.

However, Cable responded: "After the actual sale of the Royal Mail itself there was a bubble of the price of the shares which I predicted at the time actually. But it subsided after a year and a lot of those people who brought shares having read in the press that they were undervalued got their fingers burnt."

Gaffney, the MP for Coatbridge, Chryston and Bellshill, insisted the sell-off had left the taxpayer worse off.

He said: "The privatisation of Royal Mail has been a disaster, leaving workers and customers worse off. This Lib Dem/Tory stitch-up has done nothing but lose taxpayers money while making a fortune for Cameron and his cronies.

"A Labour government would take Royal Mail back into public ownership and deliver a service that works for the many, not the few."