Main opposition party leader Rep. Moon Jae-in upped the ante against his rival party Monday, saying he would attend the hearing for an investigation into an overseas resource development project, and demanded former president Lee Myung-bak join him.

“The Saenuri Party insisted that the former president Lee would attend the hearing as long as I joined him. Fair enough. I will attend the hearing, and you should join me,” said Moon from the New Politics Alliance for Democracy.

The ruling party, however, rejected the demand. “It is nothing but an attempt to play politics,” said Rep. Kim Mu-sung, leader of the ruling Saenuri Party. “If the allegation proves to be true, then he (former president) should attend the hearing. So far, no allegation has been proven. I can only imagine that they (opposition party) don’t want to continue the committee anymore,” said Kim.

Moon’s remarks come amid a political tug-of-war surrounding the investigation into an overseas resource development project, otherwise known as “energy diplomacy,” which has been under fire for causing massive losses and wasting taxpayer’s money.

Last December, the National Assembly set up a committee to investigate if there were any wrongdoings in the project. The two major parties, however, have been at odds over how to run the committee, particularly regarding a hearing for key players, including former President Lee.

The opposition party has constantly demanded the former president should attend the hearing, saying he has been in charge of the project from the beginning.

The party has also asked other key aides to Lee to attend. It urged the committee to extend its service beyond the expiration date of April 7, noting the failure to find anything until now.

“President Lee spearheaded the energy development project. I think he has an obligation to answer the allegations. I urge him to come out and face the truth,” said Moon.

“I also want to hear the response of chairman Kim, the leader of ruling Saenuri Party, to my request,” Moon added.

As for the extension of the committee’s operation date, the ruling party left it open for discussion. “The party will discuss the matter with the committee’s members,” said Rep. Yoo Seung-min Saenuri Party Floor Leader.

The project has been the most talked-about political scandal in Korea. It has cost 31.4 trillion won ($28 billion) in taxpayer’s money, according to Board of Audit and Inspection of Korea.

By Yeo Jun-suk (jasonyeo@heraldcorp.com)