Shigeru Ishiba, the No. 2 in the ruling Liberal Democratic Party and a potential rival to Prime Minister Shinzo Abe in the party's next leadership race, is ready to turn down Abe's offer of a Cabinet post, a senior LDP official close to Ishiba said Saturday.

At a meeting likely to be held this week between the two, Abe is expected to convey his plan to relieve Ishiba of his position as LDP secretary-general and ask him to instead become state minister in charge of security-related legislation in a Cabinet reshuffle next month.

But Ishiba has told close aides it would be difficult to take up a ministerial post unless his strongly held beliefs about defense policy are accepted by Abe, the official said. Ishiba, a former defense minister, is expected to voice this to Abe in their meeting.