Big-name firms are "screwing" small suppliers, Liberal Democrat economics spokesman Vince Cable said today as he backed calls for action in tomorrow's Budget to secure quicker bill payments.

The Federation of Small Businesses (FSB) wants offenders to be "named and shamed" for late payments after its research found more than a third of firms were being forced to wait longer.

With 120 closing every day as the recession bites, the FSB said urgent action was needed to make clear larger outfits could not treat smaller firms as "an external source of credit".

Mr Cable singled out supermarket giant Tesco, which today posted record annual profits of more than £3 billion, as one of the key offenders.

In an interview with a new website for entrepreneurs, he said: "Government departments have been told they have to pay within 10 days, haven't they? But it's uneven.

"Local authorities are doing the same thing. But then some of the really big commercial operations like Tesco are behaving outrageously.

"It's difficult to enforce these things but if it could be, I would welcome that," he told smarta.com - which is backed by BBC Dragon's Den stars Theo Paphitis and Deborah Meaden.

Asked about reports that high street retail and pharmaceutical chain Alliance Boots upped its payment timescale last year from 30 to 75, he said: "These big chains are just screwing their suppliers.

"There are penalties for late payment under existing legislation, but actually getting those enforced is difficult."

The Government launched a "prompt payment" code last year with an appeal from Prime Minister Gordon Brown after a pledge that the public sector would speed up payments.

But FSB National Chairman John Wright said it appeared not to be working.

"Our research shows that over a third of small businesses are waiting longer to be paid for private sector work," he said.

"This comes despite the Government-backed Prompt Payment Code, launched last November, which called for fairer payment practices between large and small businesses.

"With around 120 businesses closing a day, effective action must be taken in tomorrow's Budget to show larger businesses that small firms are not an external source of credit.

"It is time for Companies House to be given the necessary clout to use powers within the Companies Act to name, shame and fine late payers and end this trend once and for all."