CONSERVATIVE proposals for an in/out referendum on EU membership are "lighting a fire" under the 28-member organisation, Philip Hammond, the Foreign Secretary, has boasted to MPs.

His outburst, in keeping with the increasingly ramped-up rhetoric of the Conservative leadership on Europe, came as Ukip leader Nigel Farage claimed next month's Rochester by-election was the most significant since the contest in 1982 for Glasgow Hillhead.

Then, Roy Jenkins took the Scottish seat, which had been held by the Tories since 1918, and secured a major breakthrough for the SDP, which only a year earlier had been formed after a break from Labour.

"It's the most important by-election in British politics in over 30 years," declared Mr Farage, who is hoping Tory defector Mark Reckless retains the seat for the anti-EU party; a result that would pile the pressure on David Cameron over his EU stance.

At Westminster, the Tories resurrected the EU Referendum Bill, which seeks to entrench in law their ­leader's promise to hold a poll on the UK's membership by 2017. It is opposed by Labour and the Liberal Democrats and earlier this year was blocked in the House of Lords.

Tory backbencher Bob Neill, who introduced the Bill, said: "It's about giving the British people a choice about something, which is fundamental to our constitutional arrangements and it is fundamental to our future."

While the Bill comfortably overcame its first parliamentary hurdle by 283 votes to nil, legislative time and the prospect of more opposition in the Lords means it is unlikely to become law.

But in his speech to MPs, Mr Hammond said: "We are lighting a fire under the European Union by this piece of legislation."

Ukip's Douglas Carswell, the newly elected MP for Clacton, using his first speech since being re-elected, insisted Mr Cameron's keynote speech 18 months ago about holding an in/out referendum was "merely smoke and mirrors".