Moon Jae-in of South Korea's main opposition Democratic United Party on Tuesday left his job as the head of an organization honoring the former president he had served, hinting at his presidential bid.

Moon, a lawyer and the former chief of staff to late former President Roh Moo-hyun, has headed the Roh foundation since 2010.

His departure is not an attempt to distance himself from the liberal leader, the 60-year-old tweeted Tuesday, rejecting media speculation.

Moon plans to reveal whether he will run for the country's highest office after May 23, the third anniversary of Roh's death, he told reporters earlier in the day.

The liberal heavyweight recently won a parliamentary seat in a district in the conservative stronghold of Busan in recent general elections, a boost to his presidential prospects.

The center-left party is expected to nominate a presidential candidate in July or August.

The eight-month presidential race, which officially kicked off Monday, will end on Dec. 19.