Parliament could suffer a devastating Windsor Castle-style fire unless a bold restoration plan is backed by MPs, officials fear as the full scale of risk can be revealed.
The Sunday Telegraph has learnt that the Palace of Westminster has seen 60 incidents that could have caused “serious fires” in the last decade.
Parliament’s “outdated” alarm system is so "unreliable" that a group of safety officers walk the estate 24 hours a day checking if any blazes have broken out.
Last year a fire near a room packed with electrical equipment broke out after a light malfunction and was only spotted because someone happened to be walking past.
Other incidents have included water dripping onto high-voltage electrical cables and power failures as a result of flooding.
The full scale of Parliament’s exposure has come to light after The Sunday Telegraph revealed ministers are planning to push restoration plans into the long grass.
Final approval on Parliament's multi-billion pound refurbishment will not come for years under Government proposals to hand plans to an Olympic-style deliver authority.
Some politicians have been infuriated by the possibility of delay and want a so-called “full decant” approved that would see MP and peers temporarily move out of Parliament.
Chris Bryant, the Labour MP who sat on a cross-party committee that backed the move, said: “This is one of the best-loved buildings in the world, a vital part of our national heritage, a symbol of democracy and the rule of law. We have to take better care of it.
“Patch and mend won't do any longer because we risk a major catastrophe to the building and the thousands who work in it and visit every year. We should do the quickest, safest and cheapest option updating disabled and public access.
“We have already delayed far too long. Any further indecision would threaten the building and those who work there and cost yet more unnecessary money.”
Ministers are expected to make proposals for restoring the Palace of Westminster – much of which dates back to rebuilding after a 1834 fire – next month through a motion to the House of Commons.
There are fears that the Tories will not select one of the three plans on the table but instead hand decision-making powers to a semi-independent “delivery authority”.
Parliamentary insiders fear delay will heighten the risk of a major fire breaking out because much of the estates’ infrastructure is more than 100 years old.
There are fears of a repeat of the 1992 Windsor Castle fire, which saw a blaze sweep through the Queen’s official residence. She later called the year her “annus horribilis”.
Royal Palaces were subsequently ordered to improve “compartmentation” - measures designed to contain a blaze in one place such as installing fire-resistant doors and floors.
However sources said that Parliament has been unable to complete the process due to logistical problems, meaning the risk still remains.
Other concerns have been passed to this newspaper. Almost 7,000 fire detectors are spread across Parliament but many are “outdated and unreliable”, a well-placed source said meaning officers have to “patrol the Palace 24 hours a day to spot any signs of fire”.
Since 2008 there have been 60 incidents on the parliamentary estate which “had the potential to cause a serious fire”. Additionally in one year alone – between September 2014 and September 2015 – there were 2,611 electrical faults reported.
One insider said that an “urgent” programme of improvements has only managed to deal with 15 per cent of electrical rooms most at risk of failure.
“This makes the likelihood of a major failure, potentially putting the safety of the building at risk, highly likely,” the source said.
“There is a real risk of fire spreading if this occurs in the wrong place, such as next to a major power supply.”
Sources stressed that there is no criticism of the fire and safety teams, who do all they can in to keep the building safe, but warned only a major restoration can solve the problem.