Britain is to have a wholly or mainly elected second House of Parliament after historic votes by MPs last night.

Decades of deadlock over reform finally ended as the Commons voted first for an 80 per cent elected second chamber and then, entirely unexpectedly, for a fully elected House.

The decisions pave the way for one of the most radical constitutional changes in British history. It is almost certain to involve the renaming of the House of Lords.

Fears that the Lords might challenge the authority of the Commons disappeared as the MPs rejected options of a 50 per cent or 60 per cent elected Lords, and instead plumped for the 80 per cent option. Then they went the whole hog and voted by an even bigger majority for a 100 per cent elected chamber, surpassing the wildest dreams of the reformers.

The majority was swelled by the decision of a number of antireform MPs to go for a fully elected House, hoping that it would so infuriate peers that they would block the whole thing.

It may still take several years for the change to an elected system to take place. The Lords will vote next week and are expected to reject elections and opt for an appointed second chamber.

With both the main parties backing reform, however, the Government is likely to bring forward legislation in the next session of Parliament for an elected House. If that were to be blocked in the Lords Gordon Brown, if he is by then prime minister, would make an elected Lords a central plank of Labour’s manifesto and David Cameron would promise at least 80 per cent.

The option of a fully elected House was backed by a margin of 113. The 80 per cent elected Lords was backed by 38 votes.

Jack Straw, the Commons leader, who has led the moves to achieve a consensus, now plans to convene a meeting of the cross-party reform group to discuss the next steps. Under current plans elections to the Lords will be be through a form of PR. This would be by party lists in the same regions used to elect MEPs, but with “partially open” lists allowing voters to rank candidates in order. Elections would be on the same day as polling for the European Parliament, once every five years.

The Government suggests that elected members serve single terms of 15 years, after which they would be prevented from standing for the Commons for at least five years.

The Commons later voted to get rid of the remaining 92 hereditary peers but left open the questions of when and how. A Tory-Liberal Democrat bid to delay this until elected members had taken their places in the reformed House were rejected by 329 to 241, majority 88. Four years ago MPs rejected all options for change but came within three votes of backing the 80 per cent option.

In last night’s votes the Tories and Lib Dems, along with many Labour MPs, backed the 80 per cent elected option.

Winding up the debate, Mr Straw denied that an elected element in the Lords would challenge the primacy of the Commons. “It is a fear that the more the other place does the less we would be able to do as though a reformed House would suck the oxygen out of this place. It will not,” he said.

Under the Government’s plan, the link between membership of the second chamber and titles would be broken. The peerage would continue as an honour but it would be unconnected with a seat in Parliament, although it is highly probable that many people of distinction holding a seat in the reformed Lords would receive this honour, the Government’s recent White Paper said.

The Government later confirmed that the abolition of the remaining hereditary peers would be included in the new Bill introducing an elected Lords. That will appear initially as a draft Bill and later become a full legislative vehicle.

Mr Straw aims to build on the momentum of last night’s vote and press ahead with a draft Bill soon. The likelihood is that after that has been subjected to prelegislative scrutiny, he will bring in another Bill in the next session of Parliament.

If the Lords were to persist in defying the will of the elected chamber he would either try to force through the Bill the following year using the Parliament Act or wait for the next Parliament. If the pledge to turn the Lords into a largely elected House was in the manifesto of both main parties peers in the end could not resist it.

The outcome is hardly what Tony Blair expected when he became Prime Minister. He was a reluctant convert to a part-elected Lords, having previously favoured an all-appoint-ed chamber. Last night he voted for the 50 per cent option and then went off for his weekly audience with the Queen, totally unaware that history was in the making. MPs who wanted change said that the MPs who voted tactically to try to scupper the whole project were looking silly.

The opponents are, however, counting on their decision to join the vote for a fully elected Lords to strengthen the opposition of peers.

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