The prime ministership will become official, authorised by Parliament

Graham Allen Labour MP

Mr Allen warns that continuing the current situation could one day result in the UK getting a "really nasty piece of work" running the country.

Ahead of his appearance in the Commons, the Labour MP was at pains to stress his 10 minute rule bill is not a reaction to Prime Minister Tony Blair's style of leadership.

In a recent book, The Last Prime Minister, Mr Allen argued that the position had gradually evolved over many years to a point where Mr Blair exercised powers "that would make Stalin blush".

Mr Allen told BBC News Online the country needed a strong premier as much as it needed a strong Parliament.

"The prime ministership has accumulated a large number of powers but there are no statutes that refer to the precise nature of those powers."

He added that the country was at risk of getting "a really nasty piece of work" at the helm without any limits on the way they could wield the potentially "awesome" powers held by UK prime ministers.

Official PM

Mr Allen wrote to fellow MPs on Wednesday explaining his aims.

Mr Allen is an advocate for constitutional reform

He wrote: "The bill helpfully pulls together in one statute all the prime ministerial powers which currently exist but are scattered in convention, custom and practise, royal prerogatives and nods and winks.

"The prime ministership will become official, authorised by parliament, and a future incumbent would be unable to continue to expand the office without parliamentary approval."

The Prime Minister (Office, Role and Functions) Bill has support from MPs from all sides of the political spectrum.

It includes a clause that will allow MPs to approve a victorious party leader before they can formally appointed by the Queen.

Hollow politics?

Mr Allen, who lost his job in the whips' office after the general election, told MPs: "We will all be stronger for recognising the central truth of British politics: that the office of prime minister towers over our democracy.

"But this mighty oak casts a long and chilling shadow over all of us who are drawn close to it.

"Its development over the last century has made a myth out of the notion of parliamentary sovereignty, a lie out of collective cabinet government and a near terminal hollowing-out of our political parties."

His bill may gain an unopposed formal first reading but stands no chance of becoming law.