JAKARTA: Indonesia’s parliament speaker resigned on Wednesday amid a major scandal in which he is accused of trying to extort shares worth US$1.8 billion from an international mining company to ensure its contract extension.

Speaker Setya Novanto has denied the allegations, including that he used President Joko Widodo’s name in his dealings with executives from the local unit of Freeport McMoran Inc, one of the world’s biggest copper and gold mining companies.

The case has focused public scrutiny on Indonesia’s parliament, which the anti-corruption group Transparency International calls one of the most corrupt institutions in a corrupt country, and could erode investor confidence in Southeast Asia’s largest economy.

“To preserve the dignity and honour of Indonesia’s house of representatives, and to create public order, I hereby declare my resignation as chairman of the House of Representatives for the period of 2014-2019,” Novanto, who plans to remain a deputy, said in a letter to a parliamentary committee.

“This letter is the basis for us to immediately close the hearing because this is in line with the formulation of the verdict that would have been taken by the ethics committee,” said Sarifuddin Sudding, a member of the parliamentary ethics committee.

Before the letter was made public, 15 out of 17 committee members had announced their views of Novanto’s conduct, with nine saying he was guilty of “moderate ethical violations” and six saying “heavy ethical violations”.

Novanto, who did not attend the committee hearing in person, was not immediately available for comment.

The government has sought to distance itself from the controversy, with President Widodo calling on authorities to conduct a transparent investigation into the allegations. The attorney general’s office is also looking into the case.