The speed with which banks adopt Single Euro Payments Area (Sepa) payments systems is crucial to the scheme's success, according to a report by Capgemini for the European Commission.

Sepa, which launched yesterday, could either save the sector €123bn (£91bn) or cost it an extra €43bn (£32bn) by 2012 - depending on how well it is adopted.

Banks must migrate rapidly if they want to make savings, said EU Internal Market and Services Commissioner Charlie McCreevy.

"The study shows the importance of all stakeholders supporting Sepa and becoming early adopters of the new products in a market-driven process," he said.

Under Sepa, all international payments in Europe will be treated as domestic transactions by 2012, improving the efficiency of the region's financial institutions.

But deadlines have slipped. Yesterday's start date was originally due a month ago. And the timetable for other elements including cross-border direct debit payments have been put back by as much as two years, as banks prove wary of investing in the necessary technology in a heavily regulated market.

There is still a lack of consumer pressure for banks to comply with Sepa deadlines, says Capgemini.

"Many banks and retailers are worried about the relatively high investments they need to make, while many potential users are simply not yet aware of the potential benefits Sepa could bring to them," says the report published today.

UK banks are already struggling to comply with the faster payments scheme – a £300m technology programme to cut banks’ three-day clearing periods to less than 24 hours.

The scheme has already been delayed by six months until May 2008 because banks were missing implementation deadlines.