The ruling Liberal Democratic Party on Tuesday declined a request from senior party lawmaker Ryu Shionoya to review a penalty given to him over a high-profile political funding scandal.
Hiroshi Moriyama, chair of the LDP's General Council, told reporters that the party decided there were no grounds to review the penalty against Shionoya.
No faults were found in the procedures for meting out the penalty, he said at a news conference.
The LDP plans to expel Shionoya if he does not submit a letter of resignation from the party by April 25.
In the scandal, many LDP lawmakers failed to report funds provided by intraparty factions, including one the late former Prime Minister Shinzo Abe once led.
The LDP on April 4 handed out penalties to 39 members.
The members include Shionoya, former chair of the General Council, and Hiroshige Seko, former secretary-general for LDP lawmakers in the House of Councilors.
Both were urged to leave the party, the second-harshest among the party's disciplinary measures.
Shionoya and Seko held senior positions in the Abe faction.
On Friday, Shionoya demanded that his penalty be reconsidered, saying it was decided based on many factual errors.
Speaking to reporters on Tuesday, Shionoya — who has said he would consider leaving the party if his request for a review of the penalty is turned down — said there has been no change in this stance.
Seko has already left the LDP.