Tony Abbott’s deputy has publicly urged him to respond to concerns about his powerful chief of staff, Peta Credlin.

Deputy Liberal leader Julie Bishop says government MPs have offered the prime minister “very frank and blunt” assessments of how his office is being run.

“The prime minister must respond to their concerns if they are valid concerns,” Bishop told the ABC on Tuesday.

“The prime minister is a smart man. He will take this into account.”

Bishop reportedly has a strained relationship with Credlin, who has angered many government MPs by centralising control and vetoing staffing decisions.

The minister described Credlin as a very powerful figure with “a lot of opinions”.

But she stopped short of joining backbench MPs who want the prime minister to dump her.

“His particular staffing arrangements are a matter for him,” she said.

Abbott has vowed things will change in his office after he fended off a party room push for a leadership spill on Monday.

He is facing a joint party room meeting on Tuesday in which the concerns about his office are likely to get another airing.

His restive backbench is also expected to grill Abbott and his senior ministers on a number of policy issues, such as the future of the unpopular GP co-payment.

Treasurer Joe Hockey is set to face some tough questions as he begins preparing his second budget, amid ongoing unhappiness with his performance.

But Bishop rejected reports Abbott may dump Hockey from the job.

“Joe’s continuing as treasurer,” she said.

Social Services Minister Scott Morrison also backed Hockey staying in the job, despite being touted as the man most likely to replace him.

Asked whether Credlin should resign, Morrison said: “That’s a matter for Tony Abbott.”

Former assistant treasurer Arthur Sinodinos – who backed the unsuccessful leadership spill on Monday – said Tuesday’s meeting would be a “new paradigm” for the government.

“I suspect you’ll find a lot of MPs on their feet raising issues,” he told ABC radio.

“I think there’s a new assertiveness on the backbench.”

Finance Minister Mathias Cormann said the party had now put its internal issues behind it.

“There absolutely won’t be any recriminations,” he said of Monday’s spill motion.

“We have to pull together.”

One of the backbenchers who pushed for the spill said the party was now getting behind the prime minister.

“Unfortunately it required something like this for the prime minister to realise there were very significant problems both in style and substance that needed to be addressed,” West Australian MP Dennis Jensen said.

– AAP