South Korea's largest party in the National Assembly has agreed to join forces with a smaller opposition party to push for impeachment of the country's president. An impeachment bill is expected to be submitted to parliament on Tuesday.

The Grand National Party, which has more than half the seats in the National Assembly, said Monday it will support an opposition move to impeach President Roh Moo-hyun. It is joining the Millennium Democratic Party in the effort.

Millennium Democratic Party officials say the bill will be submitted Tuesday and a vote could be held the following day.

Although the two parties - as a combined force - theoretically have enough votes to introduce the bill and to impeach the president, it is unclear whether enough legislators will actually support the effort.

Political observers in South Korea say the parties have internal feuds and lawmakers also have one eye on the April 15 parliamentary election.

The impeachment talk comes after the National Election Commission ruled last week that Mr. Roh violated the law by speaking in favor of the Uri Party ahead of the parliamentary election. The commission, however, imposed no punishment.

Mr. Roh was a member of the MDP until last September and is expected to join the Uri Party soon.

The MDP had given the president a Sunday deadline to apologize for violating the election law, which he has refused to do. Instead, he is calling for the law to be revised to allow the president to more freely express his political views. He also has said the his remark supporting the Uri Party was a minor infraction, noting that the Election Commission was split over what he said.

The president's supporters call the impeachment push an outrage and are vowing to fight it.

Also on Monday, prosecutors said the president's campaign is suspected of having accepted more than $2.5 million worth of illegal funds from the Samsung Group before the 2002 election.

A senior prosecutor says the investigation is continuing, hinting at further revelations of illegal donations involving Mr. Roh's aides.

President Roh previously said he would resign if his supporters were found to have collected more than one-tenth of the value of illegal funds raised by the opposition. Mr. Roh, a former human rights lawyer, came to office on a platform of ending South Korea's tradition of corruption in politics.