Key decisions over the euro are being held up because Tony Blair and Gordon Brown have yet to agree a common position, it has been claimed.

Treasury officials have yet to complete their assessment on Britain's entry to the euro because the prime minister and the chancellor have yet to make the "political" judgments required.

"The work cannot be finished until those involved in writing the conclusions know in which direction they should go," the Telegraph quotes a "senior source" as saying.

"That depends on a meeting between the prime minister and chancellor taking place."

Brown revealed to MPs on Wednesday that that the government would be carrying out four key studies to aid the assessment of the economic case for or against euro entry.

The studies will cover exchange rate and macro economic adjustment, what might happen in the change-over period if the currency gets the green light and the framework of the five tests.

On Monday, the chancellor will publish a progress report on economic reform in Europe, which will include work on how eurozone countries are reforming their labour markets.