Former Chancellor Sajid Javid told MPs he resigned because he was unable to pick his own special advisers.

In a statement to the Commons following his resignation, Mr Javid said: "It has always been the case that advisers advise, minsters decide and ministers decide on their advisers.

"I couldn't see why the Treasury, with the vital role that it plays, should be the exception to that."

Speaking from the backbenches for the first time in eight years, Mr Javid said he wanted to explain to MPs first why he resigned.

He said: "I will also continue to champion the causes I believe in most, albeit it from outside the Government.

"I confess that I had hoped to have a little longer to make a difference from the inside.

"So with thanks for your permission to speak Mr Speaker, I thought it would be appropriate to briefly explain first to the House why I felt that I had to resign as Chancellor of the Exchequer."

Mr Javid added: "A Chancellor, like all cabinet ministers, has to be able to give candid advice so he is speaking truth to power.

"I believe that the arrangement proposed would significantly inhibit that and it would not have been in the national interest.

"So while I was grateful for the continued trust of the Prime Minister in wanting to reappoint me, I am afraid that these were conditions that I could not accept in good conscience."

In an apparent reference to Boris Johnson's chief adviser Dominic Cummings, he said: "Now I don't intend to dwell further on all the details and the personalities... the comings and goings if you will."

He added: "I very much hope that the new Chancellor will be given space to do his job without fear or favour.

"And I know this Mr Speaker, that my right honourable friend for Richmond (Rishi Sunak) is more than capable of rising to the challenge."

Mr Javid continued: "My right honourable friend the Prime Minister has won a huge mandate to transform our country and already he is off to a great start - ending the parliamentary paralysis, defeating the radical left, getting Brexit done, a points-based immigration system and an infrastructure revolution."

He added: "We need a resolute focus on long-term outcomes and delivery, not short-term headlines. The treasury as an institution, as an economic ministry should be the engine that drives this new agenda."

Mr Javid said: "But the Treasury must also be allowed to play its role as a finance ministry with the strength and credibility that it requires."

He added: "At a time when we need to do much to level up across generations it would not be right to pass the bill for our day-to-day consumption to our children and grandchildren.

"And unlike the US, we don't have the fiscal flexibility that comes with a reserve currency, so that's why the fiscal rules that we are elected on are critical.

"To govern is to choose, and these rules crystallise the choices that are required to keep spending under control, to keep taxes low, to root out waste and to pass that fitness test that was rightfully set in stone in our manifesto on debt being lower at the end of the Parliament."

Mr Javid concluded by insisting he looks to the future with "great optimism", adding: "We on these benches have a shot at achieving nothing less than wholesale renewal for our economy, our society, and for our country."

He went on: "I know that this is a shared vision and I firmly believe that the Prime Minister has the tenacity, the energy and the skill to see it through.

"I want to leave the House in no doubt that he has my full confidence, and the Government my full support to get it done."

Prime Minister Boris Johnson, raising a point of order, thanked Mr Javid for his speech and "immense service" to the country before insisting his colleague has "friends and admirers on all sides of this House of Commons".