Pakatan Harapan has refuted Prime Minister Najib Abdul Razak's allegation that its manifesto will increase the nation's debt.

The opposition coalition's chairperson Dr Mahathir Mohamad argued that the allegation is baseless because Harapan has not been given the opportunity to govern the country.

“It was Najib who raised the nation's debt as prime minister. Our job is to reduce it," he said.

Mahathir also told reporters at the opposition leader's office in the Parliament building that Najib had deceived the public with 1MDB's RM42 billion debt.

“(When prime minister) we did not form a company that exceeded the debt ceiling. The government has a ceiling, and debt cannot exceed this, as it is determined by Parliament.

“But Najib formed 1MDB, which does not have to abide by this debt ceiling. Have we heard of the government lying like this before? We have not. But Najib did it.

“If the debt needs to be increased, Najib is the one to do it. He is clever at doing that,” he said.

Last month, Najib defended 1MDB's RM42 billion debt by saying the money never disappeared, unlike the RM31 billion lost by Bank Negara in the foreign exchange scandal during Mahathir’s tenure.

In January, however, the prime minister admitted to certain "failings" in the management of 1MDB.