Germany's embattled Christian Democrats threatened today to take legal action against Helmut Kohl as they stepped up pressure on their disgraced leader to reveal the sources of secret slush funds he controlled while chancellor from 1982 to 1998.

Party Chairman Wolfgang Schaeuble said the financial penalties facing the Christian Democratic Union (CDU) because of Kohl's transgressions could force the party to sue him to recover lost funds and stave off potential bankruptcy. As the former head of the party, Kohl has "a legal duty" to disclose all the financial transactions, Schaeuble said.

But at a meeting with 4,000 supporters in Bremen, a combative Kohl spurned those warnings and vowed to uphold his "word of honor" to protect the anonymity of benefactors who donated more than $1 million to secret party accounts that he managed during his 16 years in power.

"These donors are respectable citizens of our land who have a reason for their behavior," Kohl said. "I gave them my word. It may be old-fashioned, but that's what I am. Not everyone understands, I know, but I must keep my word."

Kohl vehemently denied that the secret funds resulted from bribes or kickbacks from people who profited from decisions made by his government--something that is now being investigated by a parliamentary committee. "I was, and I am, not corruptible and not for sale," he said. "Everything you read or hear to the contrary is pure nonsense."

As the funding scandal escalated, German prosecutors said they were investigating whether a senior accountant for the Christian Democrats who committed suicide Thursday may have feared exposure for embezzlement or been involved in diverting party funds.

Wolfgang Huellen, the chief financial officer of the CDU's parliamentary delegation, hanged himself in his Berlin apartment and left behind a suicide note that contained passages that prompted a probe into the possibility of embezzlement or breach of trust, according to Berlin prosecutor Stefan Wolf.

Wolf refused to provide further details, but Berlin newspapers reported that Huellen's note expressed his fears about a potential financial audit because of the scandal and his misgivings about fund transfers from the parliamentary group's account.

Christian Democratic legislator Joachim Hoerster, who served as Huellen's supervisor and announced his death, said the suicide note referred to "personal motives" for taking his life. Huellen's wife and two sons remained in Bonn after he moved with the government to Berlin last year, and some colleagues said he may have been depressed by their separation.

Until now, Huellen had not been publicly implicated in the funding scandal. However, Parliament has raised questions about the legality of a $570,000 cash transfer from the CDU's legislative faction to party headquarters in 1997. But that transfer, which almost certainly would have involved Huellen, was not considered related to more serious bribery allegations now being investigated.

The unfolding scandal has revealed a complex web of banking connections that the Christian Democrats maintained with Switzerland and Liechtenstein during the Kohl era. Party leaders said an audit to be published this weekend showed those links clearly served money-laundering purposes.

Roland Koch, who recently became the Christian Democratic party chief in the state of Hesse, said today he discovered more than $2 million had disappeared from party coffers between 1993 and 1997. He said he was astounded by the complexity of secret bank accounts the party's Hesse branch had set up in Switzerland nearly two decades ago.

The money apparently was shifted from CDU accounts in Frankfurt and placed under the control of a secret foundation called "Wren" with assets of $9 million that was set up in Vaduz, Liechtenstein--even though the funds themselves remained in Switzerland until they were returned to Germany. The foundation was run by Horst Weyrauch, a party accountant and one of Kohl's closest friends.