Anders Fogh Rasmussen, the Danish premier, sought political support on Tuesday for a referendum on adopting the European single currency, after the central bank revealed that it has used almost a fifth of its reserves last month to defend the krone's peg to the euro.

"I'm convinced that we need broad support in parliament to hold a referendum, because it's about the Danish currency and about stability and safety," he said.

Opinion polls show growing support among Danes for the euro, with just over 50 per cent in favour, but the government fears this majority could disappear during a referendum campaign unless it has broad political support.

Mr Rasmussen said he would begin talks with opposition parties over the coming days, but refused to be drawn on a date for a referendum.

Danes rejected the euro in a plebiscite in 2000. A second rejection would be very difficult to reverse, and could cause severe financial turbulence in the current environment.

The opposition Social Democrats back the euro, but Mr Rasmussen wants to secure the support of the leftwing Socialist People's party, which ranks a strong third in opinion polls. The party has warmed to the euro during the financial crisis but remains deeply divided on the issue.

The centre-right government has promised a referendum on the euro before November 2011 when its term ends, arguing that Denmark's monetary independence excludes it from eurozone economic decisions that affect it. The krone has long been tightly pegged to the euro and the central bank usually shadows European Central Bank interest rate decisions within a few hours.

However, in the past month the Danish central bank has had to sell foreign exchange and raise interest rates twice to shore up the krone. On Tuesday, the it said its foreign exchange reserves had fallen by Dkr27.8bn to Dkr132.4bn ($23.1bn, €17.8bn, £14.4bn) in October because of its interventions.

Pressure on the krone has provided the government with a new argument that staying outside the eurozone also has real economic costs.

The spread between Danish interest rates and the ECB's was just 25 basis points in May; it is now at an all-time high of 175 basis points. This could widen further if the ECB cuts rates as expected by half a per cent on Thursday and the Danish central bank does not follow.

The interest rate rises threaten to push housing prices down further, hurt consumer spending and depress an already stagnating economy. Denmark only emerged from technical recession in the second quarter and growth this year and next is expected to be less than 1 per cent.

The Danish government had hoped to hold a referendum this September on abolishing the country's other opt-outs from the Maastricht treaty, covering closer EU co-operation on defence and justice and home affairs, but put this on hold when Ireland voted against the Lisbon treaty. The government is waiting for Ireland to explain how it will proceed before it tries again, so the more controversial euro referendum could now come first.