Chris Grayling is to accuse David Cameron of undermining Britain's position by making key errors in his EU renegotiation.

In a damning critique of the package secured by the Prime Minister from Brussels, Leader of the House Mr Grayling will insist it failed to address any of the "fundamental problems".

He will warn that Mr Cameron's concession that the UK would not stand in the way of eurozone integration could put it in a "worse situation" than before.

The Cabinet minister's comments, due in a speech in Westminster, could herald a further escalation of tensions between senior Tories ahead of the referendum on June 23.

Mr Grayling - one of six members of Mr Cameron's top team backing Brexit - will warn that the UK would still be choosing to stay in an "unreformed EU which will hoover up more money and more power at every opportunity it gets".

"The degree to which the European Union now governs our lives is not changed by this agreement," he will say.

"The renegotiation has not returned powers to Parliament or the people elected and accountable to it."

Mr Grayling will add: "The agreement that the Prime Minister reached three weeks ago provides us with a little insurance for the future.

"It does not sort out the fundamental problems of our relationship with the EU today or prevent us from being affected by the changes that lie ahead."

Mr Grayling said the package would leave "unelected EU judges in control of a whole raft of our laws".

"There will be more and more laws passed at a European level. It is an illusion to think that those laws will not affect us," he is to add.

The minister will also echo fears expressed by Tory MPs this week that the deal removes the right of future prime ministers to use Britain's veto during treaty negotiations.

"One of the inadvertent consequences of the renegotiation discussions is that we have agreed that Britain 'shall not impede the implementation of legal acts directly linked to the functioning of the euro area'," Mr Grayling will say.

"This is a significant - and underappreciated - loss of leverage. We now lack a key tool in preventing further EU integration - which we might be dragged along into. In fact we may be in a worse situation than we were before."