LIMA, PERU (BLOOMBERG) - Peru's congress will vote on whether to start impeachment proceedings against President Martin Vizcarra after lawmakers accused him of lying and seeking to obstruct a graft probe involving government officials.

Lawmakers will meet at 10am in Lima on Friday (Sept 11) to debate the motion, which calls for Mr Vizcarra's impeachment on the grounds of "moral incapacity".

A potential vote on his ouster would take place at a later date, after his defence in the country's single-chamber congress.

Mr Vizcarra's opponents need 52 votes to start impeachment proceedings against him.

If the motion is admitted, the opposition needs 87 votes to him force out.

So far, six out of nine parties with 95 votes in the 130-seat congress signed the motion, reported El Comercio newspaper.

Speaking to Parliament late Thursday, the head of congress, Mr Manuel Merino, called for the Armed Forces and the wider population to remain calm, adding that lawmakers will act in accordance with the constitution.

The political turmoil threatens to deepen a crisis triggered by the coronavirus pandemic, which caused Peru's gross domestic product to contract 30 per cent in the second quarter, the deepest slump of any major economy.

It follows a series of clashes between the opposition-controlled congress and the executive as Peru heads to general elections in April.

Earlier this week, lawmakers presented a motion to remove Finance Minister Maria Antonieta Alva from her post, alleging she didn't do enough to prevent the economic slump during the pandemic.

"This political crisis adds another layer of uncertainty to an economy already stressed by the severe pandemic impact on all grounds," JPMorgan Chase & Co's analysts Diego Pereira and Lucila Barbeito wrote in a report.

"This new congress has proved even more antagonistic to the government than the previous one, and thus the likelihood of a deeper institutional crisis could not be ruled out."

Peru's sovereign bonds due in 2050 dropped less than one per cent in early trading, heading to their lowest close since Aug 31.

LEAKED RECORDINGS

Prosecutors and lawmakers earlier this year began probing alleged irregularities in the government's hiring of a little-known singer to give motivational talks at the Culture Ministry.

The singer, Mr Richard Cisneros, is alleged to have used contacts in the presidential palace to obtain contracts totalling about US$50,000 (S$68,334), despite lacking experience.

Mr Vizcarra, who doesn't have a party to defend him in congress, said in a Thursday televised address that the release of the tapes was part of a plot by political opponents to remove him from power.

"If you want to impeach me, here I am. With my head held high and with my conscience clear," he said.

"Nothing of what was presented today, illegally, constitutes grounds for impeachment. I'm not going to resign. I don't run away."

Mr Vizcarra's predecessor, Mr Pedro Pablo Kuczynski, resigned after an opposition lawmaker released videos that showed his allies apparently negotiating votes to stave off his impeachment.

Since replacing him in 2018, Mr Vizcarra has frequently clashed with the opposition-controlled congress after he pushed for reforms designed to stamp out corruption in the judicial and political systems.

Prosecutors investigating the case searched offices at the presidential palace in Lima on June 1.

Mr Vizcarra turned down a request to testify to a congressional committee last week.

In his national address, the President said that while he knew Mr Cisneros, he had nothing to do with his hiring.

He said the tapes played in congress earlier on Thursday had been "edited and manipulated".

In one excerpt, Mr Vizcarra appears to say Mr Cisneros made several visits to the presidential palace and instructs his staff to say only a couple of them happened.

In another recording, Mr Cisneros appears to brag about having close ties with Mr Vizcarra, claiming credit for the President's rise to power and for his decision to close congress last year.