Indonesia ruling party chief quits over graft accusation
"I quit as the chairman of the Democratic Party," he told reporters in a press conference.
Urbaningrum, 43, was named a suspect Friday for allegedly receiving "gifts or a promise of gifts" in a graft case linked to the construction of the Hambalang sports centre project near Jakarta, worth around 1.17 trillion rupiah ($120.5 million).
His resignation was widely expected as all Democratic Party officials had recently signed an "integrity pact" to give up their posts if named a graft suspect.
Maintaining his innocence, Urbaningrum said he would go through the necessary legal procedures.
It was widely known that President Susilo Bambang Yudhoyono, patron of the ruling Democratic Party, had not favoured him for the chairman post in 2010, and on Saturday the accused hinted that he believed the graft accusations were related to that.
The allegation involving Urbaningrum is the latest scandal to hit the ruling party and is a further embarrassment for the president, who won a landslide victory on his re-election in 2009 on a corruption-fighting platform.
Legal graft cases surrounding the Democratic Party have dogged its popularity, which slumped to a mere eight percent in December last year from about 21 percent in 2009. Elections are due in 2014.
At the beginning of December, the sports minister Andi Mallarangeng, who used to be the presidential spokesman, was forced to resign after being named a suspect in the same case.
He was the first minister to step down over graft allegations since the country's powerful Corruption Eradication Commission (KPK) began operating in 2003 with a mandate to crack down on rampant graft.
The party's former treasurer Muhammad Nazaruddin was jailed last April for four years and 10 months over a separate sports graft case.
The Hambalang sports centre was built following a tender process that has been publicly questioned. The case has dogged Indonesia's politics and Democratic Party ever since the KPK kicked off an investigation into the sports complex development in 2010.
While the country has shown an improvement in tackling corruption over the past decade, that success has dwindled in recent years.
Last December it slid to 118th of 176 countries ranked by Transparency International's annual index, which rates the least to the most corrupt states.