Foreign companies could be exempt from new anti-corruption laws

Under the Bribery Act, approved by parliament last year, companies with any British interests would face unlimited fines unless they adopt "adequate procedures" to prevent bribery.

Writing in the Financial Times, Clarke said it would be up to the court to decide whether or not a company is considered to be "carrying on a business" in Britain.

"Mere listing on the London Stock Exchange, or just the fact of having a UK incorporated subsidiary, would not necessarily mean the act applies," Clarke said.

"But to be clear: this is not a 'carve-out.' Under the terms of the act, it has always been a decision for the courts."

Clarke will publish guidance later on Wednesday, originally expected in January, detailing how companies should comply with the rules to avoid prosecution.

"The ultimate aim of this legislation is to make life difficult for the minority of organisations responsible for corruption, not to burden the vast majority of decent and law-abiding businesses," Clarke said.

He said small companies would not need "an army of lawyers" to manage bribery risks.

"They can rely heavily on simply telling staff, verbally," he said.

The government had to delay implementation of the law, originally due in April, after companies complained the rules were too strict and created uncertainty for multinationals and firms seeking business abroad.

A government spokesman told Reuters on Monday that the law will come into force in late June or early July.

Clarke said cases will be brought where they are in the public interest.

"I do not expect a large number of prosecutions, and certainly not for trivial cases based on overzealous literalism," he said.