Labour risks losing the next general election if it goes ahead with a euro referendum in the current parliament, a senior trade union leader has warned.

TGWU general secretary Bill Morris said Tony Blair should concentrate instead on improving the public services.

The euro will still be there in the next Parliament

Bill Morris

Mr Morris told BBC Radio 4's Today programme: "The prime minister should rule out a euro referendum, guarantee a third term and then return to the issue."

The government has given itself until next June to rule on its five economic tests for entering the single currency.

Growing unrest

If the tests are met, Tony Blair has said he will call a referendum.

Former Scotland Office Minister George Foulkes said on Monday the vote will take place next October.

Gordon Brown will rule on the five economic tests

But this was later denied by Downing Street, which insisted no date had been set.

Delegates at next week's TUC Conference are expected to back the government's position on the euro, by passing a resolution recommending entry if the five tests are met.

But Bill Morris' intervention will be seen as a sign of growing unrest within the trade union movement on the issue of the single currency.

Mr Morris, a close ally of Chancellor Gordon Brown, and a well-known euro sceptic, said voters would hit back at Labour if it concentrated on a euro campaign at the expense of public services.

'Barely register'

Writing in Tuesday's Times newspaper, he said: "The euro will still be there in the next Parliament.

Five economic tests

Economic convergence Economic flexibility Effect on investment Impact on financial services industry Good for employment?

"If its energies, resources, it's time and its focus deviate from the task of delivering world-class public services, then a Labour government may not be."

Postponing the euro referendum would "barely register on the Richter Scale of voter indignation", Mr Morris added.

His words come as research published by the anti-euro No Campaign suggests the Treasury's five economic tests mean little to voters.

Ad campaign

Only 17% of those questioned in the ICM poll recognised the phrase, with 2% correctly identifying one or more of the tests.

No Campaign director George Eustice said: "Pro-euro ministers have convinced themselves that voters take the five tests seriously and will change their minds as soon as Gordon Brown gives the nod.

"But this is just another case of politicians over-estimating their own importance."

The No Campaign has this week launched an advertising campaign to coincide with the 10th anniversary of Britain's exit from the European Exchange Rate Mechanism (ERM).