Main opposition Democratic Party(DP) policy chief Jin Sung-joon said his party will not agree to expanding the state budget for prospective oil and gas drilling in the East Sea, without finding the truth behind allegations surrounding U.S. geoscience research analysis firm Act-Geo.

At a party meeting on Tuesday, Jin referred to allegations that the Korea National Oil Corporation(KNOC) signed a contract with the firm, despite its four-year corporate suspension following failed tax payments. The policy chief also mentioned allegations that Act-Geo is a paper company.

Jin then accused the energy ministry of attempting to conceal related documents amid growing allegations, and refusing lawmakers' request for their submission.

He said the main opposition plans to thoroughly verify the allegations through the parliamentary trade and energy committee as the drilling project is expected to cost an astronomical amount from the state budget.

Jin reiterated a warning that there will be no budget allocation without the government's document submission.