LONDON (CNN) -- While most of Europe celebrated the launch of a new common currency Monday, Britain watched the euro's first trading day from a comfortable distance.

The United Kingdom is one of four European Union nations not participating in the new currency, at least for the time being.

Although British banks are offering mortgages in euros, they will only be available to those who are paid in the currency.

British Prime Minister Tony Blair wrote in Monday's Wall Street Journal that the time is not yet right for Britain to join. Blair has promised a referendum, but not yet set a timetable for it.

Opinion polls indicate the public is deeply divided on scrapping the pound for the euro.

"I think there's no place for us if we're not part of Europe," said Denise Hollingberry on a street in London. "I don't see what people think is going to happen if we stay outside and miss this opportunity, and then get involved later on worse terms."

Others disagreed.

"No, I don't think they should be (involved in the euro)," another woman said. "The whole country's going down the drain."

Even astrologers are getting into the act, endorsing Britain's caution.

Financial astrologer Roy Gillett has studied the euro's star charts. He said the currency's first few weeks will be marked by conflict between speculators and more disciplined traders.

"The first couple of weeks, up to the 20th, are dominated by a Mars-Saturn opposition," Gillett said. "Now Mars is the speculators' planet, it's that willingness to take a risk, and Saturn is the disciplinarian of the market, it's about control, order, proper legitimate way of doing things."

But Gillett said the euro could not really be judged until it overcomes an expected burst of speculation in March 2000.

Despite Britain's reluctance, the other three nations sitting out the euro showed growing interest in joining.

In both Sweden and Denmark, there are signs that public referendums to decide the issue could be held before 2001.

Greece, which wanted to join the euro launch but failed to meet economic requirements, saw bond and stock markets soar, while its drachma was boosted by growing confidence the country would join the monetary union within two years.

Reuters contributed to this report.