Japanese Prime Minister Shigeru Ishiba denied talk on Wednesday that he would quit after a source and media reports said he plans to step down following a bruising upper house election defeat.

The 68-year-old leader said media reports that he had already decided to resign were “completely unfounded.”

Ishiba chose not to quit straight after the election to prevent political instability as an August 1 deadline for clinching a trade deal with the U.S. approached, a source close to the prime minister said, asking not to be identified because they are not authorised to talk to the media.

Ishiba and Trump unveiled a trade deal on Tuesday that lowers tariffs on imports of Japanese autos and spares Tokyo punishing new levies on other goods.

Ishiba will announce his resignation next month, Japanese media reported earlier.

If he does go, his departure less than a year after taking office will trigger a succession battle within the ruling Liberal Democratic Party as it contends with challenges from new political parties, particularly on the right, that are stealing its support.

Among them is the “Japanese First” Sanseito far-right group which surged in Sunday’s vote, growing its representation in the 248-seat upper house to 14 from one. The party has attracted voters with pledges to curb immigration, slash taxes, and provide financial relief to households squeezed by rising prices.

Ishiba defeated hardline conservative Sanae Takaichi in a party leadership runoff last year. Whoever succeeds him as head of the LDP would have to govern without a majority in either house of parliament following the government’s lower house election defeat in October.

Any new leader’s immediate priority will be to secure support from enough opposition party lawmakers to win confirmation as prime minister.

An incoming leader is unlikely to call a general election straight away, instead holding off on strengthening the party’s appeal before seeking a mandate from voters, the source said.