Former second finance minister Ahmad Husni Hanadzlah's long list of questions related to 1MDB in the Dewan Rakyat last night suggests he was kept in the dark all this while, two opposition MPs say.

"Wouldn't he have known the answers since he was second finance minister during the material time? Or does it mean key information about 1MDB was kept from him?

"1MDB seemed to be a top secret operation that only one person in cabinet - the PM who is also the finance minister - knows about," said Petaling Jaya Utara MP Tony Pua when met at the Parliament lobby today.

Husni was appointed second finance minister in April 2009, a few months before 1MDB's first major deal - the short-lived joint-venture with PetroSaudi International.

He resigned from cabinet and quit all his positions in Umno in June 2016. He remains an Umno member and is currently serving his fifth consecutive term as the Tambun MP.

During the debate on the Budget 2017 speech yesterday, Husni had asked the government why 1MDB was formed and if any action would be taken against 1MDB's management for channelling the company's funds to the "wrong places".

He also asked why the government was only being paid in 2020 for the sale of a 60 percent stake in the Bandar Malaysia project to a Chinese firm.

Husni also queried the government if Malaysia would be portrayed in a negative light should 1MDB lose its arbitration case in London to Abu Dhabi-based International Petroleum Investment Co, which is seeking over US$6.5 billion from 1MDB.

Why the deferred payment?

Husni is among the very rare backbenchers to have questioned the government's handling of 1MDB.

When met at the Parliament lobby today, Semporna MP Shafie Apdal said he was glad that Husni had raised these issues in the Dewan Rakyat.

"We questioned him a lot in cabinet. I remember that some of those questions I asked was not met with answers. But I'm glad he said what he said.

"We hope this will provide us with further clarifications," said Shafie, who was rural and regional development minister between April 2009 until his removal in July last year.

Among others, Shafie said the matter that the government must urgently explain was the deferred payment for the sale of equity in Bandar Malaysia.

"This is a matter that is close to the heart of the armed forces personnel. When I was deputy defence minister, we held on to the land. Now we are selling it to investors from China and we will only be paid in 2020... Why is this so?" asked Shafie.

Pua said that it was very likely that Husni had tried to ask the same questions while he was in cabinet but didn't get any answers.

"I've tried for five years and got nothing. It is sad that a former minister has to resort to this channel," said Pua.