The corruption scandal engulfing senior management at Samsung, the electronics manufacturer, gathered new momentum today after a former adviser to President Roh of South Korea said that he was a offered a cash bribe by the company.

Lee Yong Chul, who served as a presidential monitor against corruption, said that he was handed 5 million won (£2,636) by an executive at Samsung Electronics — apparently as a "holiday gift" — but immediately returned it when he saw how large the sum was.

"I was outraged by Samsung's brazenness, by its attempt to bribe a presidential aide in charge of fighting corruption," Mr Lee said in a statement issued by a campaign group pressing for charges to be brought against Samsung.

A spokesman for Samsung Electronics, a subsidiary of Samsung, told The New York Times: "We are trying to find out the facts around these allegations."

Mr Lee's assertion comes barely a week after a former chief lawyer at Samsung claimed that the company had systematically bribed a number of senior South Korean Government officials, including prosecutor and tax collectors, as well as presidential aides, members of the judiciary and journalists.

Kim Yong Chul, who served as Samsung's chief counsel for seven years, said that among the officials who received bribes on behalf of the Samsung chairman was Lim Chai Jin, South Korea's new chief prosecutor.

Mr Lim has denied the allegations.

Other officials to have been named include the head of the country's Independent Commission Against Corruption, who was appointed by President Roh in August, and the director of the Central Investigation Bureau, which examines corruption charges against politicians.

Both have refuted the claims.

Prosecutors are investigating Mr Kim's allegations, but opposition parties say that an independent counsel is necessary and have drawn up legislation that would open a fresh investigation.

President Roh's office has dismissed appeals for an independent prosecutor, calling them a political manouevre.

South Korea's presidential election is to take place on December 19.

Mr Lee, the former anti-corruption official, said that he received his bribe in January 2004, after a Samsung Electronics executive approached him and asked whether the company could send him a gift for the holiday season.

Mr Lee said he accepted, thinking the gift would be small, but when he saw the cash returned it immediately, with a protest note.

The Samsung executive then apologised, saying he had not known that the gift contained cash.

Mr Lee said that he had gone public with his claims after reading the statements made by Samsung's former chief lawyer, adding that he believed Mr Kim's assertion that Samsung's bribery efforts had been systematic.

He issued his statement through a campaign group, the National Movement to Unveil Illegal Activities by Samsung and its Chairman, which said: "This is proof that Samsung's bribery has reached not only prosecutors but the very core of political power."

President Roh's office told The New York Times that the group's claims were "pure speculation".

A spokesman for Samsung was not immediately available for comment.

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