MANILA (Reuters) - Philippine President Rodrigo Duterte on Wednesday vowed to file an impeachment complaint against the head of the country’s anti-graft body after she launched an inquiry into allegations that he has billions of pesos in undeclared funds in bank accounts.

Philippines 'President Rodrigo Duterte stands at attention during a courtesy call with the Association of Southeast Asian Nations (ASEAN) Economic Ministers in Manila, Philippines, September 6, 2017. REUTERS/Pool/Mark Cristino

The firebrand leader said he also wanted the chief justice of the Supreme Court removed because she allowed herself to be used as a tool by his political opponents, who are conspiring to unseat him.

“We will file an impeachment case against her,” Duterte told reporters, referring to Conchita Carpio-Morales, who heads the Office of the Ombudsman, the government’s anti-graft agency. “I would tend to believe she was part of the conspiracy.”

Duterte was angered when the agency confirmed last month it was examining allegations that he failed to disclose the full extent of his wealth in a mandatory asset declaration when he was mayor of a southern city prior to becoming president.

“In the end, they will discover, to their sorrow, there is no such amount,” he said, challenging Carpio-Morales and Supreme Court Chief Justice Maria Lourdes Sereno to join him in making public their own bank accounts and resigning from office.

He said Sereno did not disclose government earnings of 30 million pesos ($588,000) for serving as a private lawyer in an airport arbitration case. Sereno already faces a pending impeachment case in Congress.

Sereno made no immediate comment, but her lawyers said they were ready to answer the complaint and prove she had not committed an impeachable offense.

An impeachment complaint against Carpio-Morales, who is the aunt of Duterte’s son-in-law, would be based on accusations of “selective justice” and the use of “falsified documents”, the president added.

Carpio-Morales’ office did not respond to telephone calls from Reuters to seek comment.

In an earlier statement, her office had said, “This office shall not be intimidated. We will nonetheless proceed with the probe as mandated by the constitution.”

In the Philippines, the president, vice president, supreme court judges, heads of constitutional agencies and the ombudsman can only be removed through impeachment on the basis of high crimes such as treason, bribery, corruption, betrayal of public trust and constitutional violations.

Duterte said the two women had conspired with members of the Liberal Party and with his critic, Senator Antonio Trillanes, who supplied the ombudsman with what he called illegally-acquired and stolen bank records.

In an interview with reporters, Trillanes denied the president’s latest allegations. “For me, Mr Duterte, do not avoid the issue of hidden wealth with this malicious allegation,” he added.

The Liberal Party made no immediate comment when contacted by Reuters.