MP Norman Lamb, who defied his party and refused to vote against the triggering of the Brexit process, will vote against the Repeal Bill.

The North Norfolk Liberal Democrat felt he could not vote against Article 50 – which set the Brexit process in motion last year – after his constituency voted in favour of quitting the European Union.

But now he has hit out at the European Union (Withdrawal) Bill calling it a 'power grab' and a threat to parliamentary sovereignty. The bill – which is having its second reading in the House of Commons and will face a vote on Monday – includes so-called Henry VIII powers which would allow ministers to pass laws quickly and without the usually scrutiny of parliament.

Mr Lamb said: 'I don't feel in a difficult position on this. I think the legislation that is being put to parliament is deeply flawed and is a power grab by ministers.

'The fundamental case put forward by the Leave campaign was about regaining parliamentary sovereignty and this completely undermines that. This is about giving power to ministers and although there are so-called sunset clauses there is no date attached to them.

'The question anyone who is supporting this bill has to ask themselves is 'if it was in the hands of your opponents would you be supporting it?' The answer is no. You have to think would you be comfortable with this way of working if someone else was in charge? I totally accept that we need legislation to implement the departure from the EU but this bill is unconscionable because it fundamentally undermines what the Leave campaign argued for – parliamentary sovereignty.'

He added that although he still accepted Britain would be leaving the EU it must not be at the expense of parliament: 'The task is for the government rather than opposition to come up with a mechanism that is not as objectionable as this – we have to be conscious that we can't bog ourselves down for years.

'I remain of the view that we have to accept the outcome of the referendum and I remain of the view that legislation is needed to implement what has been decided but I am not going to sign up to any legislation how ever offensive it is in terms of undermining parliament.'

Both Labour and the Liberal Democrats have signalled they will oppose the bill.