A Scottish Conservative peer is to lead a review into the House of Lords after David Cameron’s government suffered a humiliating defeat over planned tax credit cuts.

Lord Strathclyde is to examine how to protect the powers of “elected governments”, Downing Street said.

David Cameron personally announced the inquiry just hours after peers voted to delay his policy.

Glasgow-born Lord Strathclyde previously chaired a commission into Scottish devolution for his party, before last year’s independence referendum.

Even before the details of the review were announced Conservative peers urged David Cameron to sack dozens of their colleagues.

They rejected suggestions that the Prime Minister should pack the House of Lords with more than 100 extra Tories.

Ministers should instead slim down Westminster’s second chamber, they suggested.

Mr Cameron is the first Conservative prime minister not to have a majority in the Lords.

Lord Norton, professor of government at the University of Hull, who has been described as the "the UK's greatest living expert on Parliament", said that there was a danger of ministers approaching the issue from "the wrong end".

"We should not be increasing in size but reducing, “ he said.

"Why not take the opportunity to slim down the size ... while addressing the point that the PM is concerned with?”, he asked MPs on the Commons Public Administration and Constitutional Affairs Committee.

Peers “already take the view that we are too large (in number), both in terms of how we are seen.. and in terms of efficiency,” he added.

Meanwhile, former Scottish Secretary Lord Forsyth of Drumlean described talk of flooding the Lords with new Conservative peers as “absolutely insane”.

The Lords was already too large and needed to be shrunk, he said.

No 10 said that the review would "secure the decisive role of the elected House of Commons".

Many Tory MPs are furious that the tax credit plans were blocked by the unelected House of Lords.

But Commons Speaker John Bercow risked Mr Cameron’s ire when he insisted that the Lords did nothing wrong.

The Chancellor George Osborne had earlier pointedly told MPs that the Lords had overreached themselves.

Mr Bercow said that “nothing disorderly” has occurred and “there has been no procedural impropriety - that would not have been allowed.”

A No 10 spokesman said: “The Government is setting up a review to examine how to protect the ability of elected Governments to secure their business in Parliament.

“The review would consider in particular how to secure the decisive role of the elected House of Commons in relation to (i) its primacy on financial matters; and (ii) secondary legislation.

“The review will be led by Lord Strathclyde, supported by a small panel of experts.”