Rep. Ahn Cheol-soo, who is running for the leadership of the ruling People Power Party (PPP), said that the presidential office is interfering in the leadership race, which is a serious matter that impairs the foundation of the country's democracy and party politics.

Ahn made the remarks on Sunday in a post on his social network, urging the top office to take a strong measure to prevent media reports that Yoon is supportive of a certain candidate, citing an unidentified senior official from Yoon's office.

Ahn made the call after media outlets reported that Ahn is not Yoon's favorite candidate citing an official from the presidential office.

Meanwhile, a key official at the top office told KBS on Sunday that it is a serious matter for Ahn to continue to drag President Yoon into the national convention and to use the term "Yoon's key aides."

According to the official, Ahn is criticized in the presidential office for describing his campaign as an "Ahn-President Yoon alliance" against the "Kim Gi-hyeon and Chang Je-won alliance." Kim is a key candidate in the leadership race.

The official said that Ahn's use of the expression "Yoon's key aides" worsens the division among party members.