Britain's planned referendum on membership of the European Union passed its first hurdle in parliament's upper house on Friday, but lawmakers warned that the bill could be killed off by delays.
The bill -- which is backed by Prime Minister David Cameron's Conservative party and guarantees a public vote on EU membership by 2017 -- passed the "second reading" stage unopposed in the House of Lords after a marathon seven-hour debate.
But there were warnings from members of the Conservatives' coalition partners, the pro-EU Liberal Democrat party, as well as opposition Labour peers that the bill could face such heavy delays that it could be scuppered altogether.
Lawmakers intend to table a series of amendments to the European Union (Referendum) Bill.
The legislation must return to the lower House of Commons and successfully pass through it by February 28, meaning that lengthy amendment debates could result in the bill running out of parliamentary time.
As a so-called "private member's bill" introduced by an individual lawmaker, as opposed to the government, parliamentary rules dictate that there is only a very small number of days on which it can be dealt with.
Cameron, under pressure from the eurosceptic wing of his party, has promised to renegotiate Britain's relationship with the 28-member bloc before holding an "in/out" referendum if his Conservatives win the next general election in 2015.
Former finance minister Nigel Lawson was among the Conservatives arguing staunchly in favour of a referendum, saying Britain's economic future lay in trade links outside Europe.
"Quite apart from the fact that the people of this country want a referendum, the people are right," he told parliament.
"They are right because of the huge change that has come about following the creation of the European monetary union and the political consequences of that decision."
But Peter Mandelson, the ex-Labour minister and former European commissioner, said Cameron had been "taken hostage" by "militant" eurosceptics within his party.
"We need to concentrate on using all of our influence and energy in building up Britain's influence in Europe, not driving Britain out of Europe," he told parliament.
Anti-British National Party activists wait for the arrival of party leader Nick Griffin at Manchester Town Hall in Manchester, north-west England on June 7, 2009
[Image via Agence France-Presse]