Jeremy Corbyn has refused to say whether members of the frontbench who defied his orders over the Government’s Brexit Bill could keep their jobs – but added is “a very lenient person”.

The Labour leader’s comments come as the party braces itself for a fresh rebellion as the EU Withdraw Bill – the legislation needed to invoke Article 50 and begin the Brexit negotiations – receives its final third reading in the Commons this week.

Last week’s vote on triggering the mechanism for leaving the EU led to the resignation of three members of Labour’s Shadow Cabinet, including Jo Stevens, Rachael Maskell and Dawn Butler.

Three party whips – responsible for party discipline – also defied orders alongside ten junior ministers on the frontbench. No decision has yet been made on whether they will retain their job after breaking ranks and rebelling against the three-line whip – the strictest possible instruction.

In total, 47 Labour MPs voted against the party’s official position.

The Independent understands Mr Corbyn will fill the now vacant positions in the Shadow Cabinet after Wednesday’s vote. But when asked on Sunday whether frontbenchers who defied party orders could keep their jobs, Mr Corbyn told BBC Radio 4’s The World This Weekend: “I’m talking to all of them. We will be announcing changes in the Shadow Cabinet in the coming few days.

“I’m a very lenient person,” he added.

Asked whether rebels would keep their jobs at the upcoming third reading, he responded: “You are asking me a very hypothetical question here. I will be making an announcement during the week.”

Clive Lewis, the Shadow Business Secretary, who is tipped by those on the left of the party as a future Labour leader, has hinted he could resign from his post if Labour’s amendments are not accepted in the Commons.

In an interview with The Independent John McDonnell, the Shadow Chancellor, added that the party abides by the “parliamentary convention whereby if someone is in the Shadow Cabinet and voted against it they resign”.

On the other ranks within the Parliamentary Labour Party (PLP), he added: “The chief whip will report after the Commons stages of the Bill itself and we’ll take into account what his recommendations are.”

Earlier on Sunday Emily Thornberry, the Shadow Foreign Secretary, indicated the party will not attempt to block Brexit, even if the party’s amendments do not get accepted in the Commons later this week.

Speaking on the BBC’s Andrew Marr Show, Ms Thornberry said: “We have said that we will not frustrate Brexit. We have got our instructions from the British people. We are democrats and the public have voted to leave the European Union.

“There are going to be negotiations happening in the next week. There are many ways in which the Government may be able to react to this that will be positive.

“On one of the amendments we have put down they may say: ‘We’re not going to support this amendment but during a speech we can give an assurance, we can speak in back channels, we can say you will get this.’

Emily Thornberry says Labour are a national party and will not frustrate will of the people

“There will need to be back channels, private conversations. There are many conversations going on now. We are speaking to Government, we are speaking to Tory backbenchers and we are trying to get a compromise that will work.”

Ms Thornberry refused to be drawn on whether the Shadow Home Secretary, Diane Abbott – who infuriated many Labour MPs when she missed last week’s vote because she said she had migraine – would face the sack if she failed to support the bill in Wednesday’s final third reading vote.

“It is a fast-moving picture. Let’s see what happens,” she said. “The whip will be decided next week. Let’s see what happens in relation to the amendments. We have a Shadow Cabinet meeting next week. It will be for the chief whip and the leader to decide what the whip is.”