The United States raised the pressure on euro zone leaders to take decisive action on solving the region's debt crisis, notably by lowering troubled members' borrowing costs, on the eve of a crucial European Central Bank meeting, according to Reuters.

President Barack Obama said he welcomed recent declarations by European leaders and the ECB on the need to do whatever is necessary to preserve the euro.

U.S. Treasury Secretary Timothy Geithner had a blunter message for the euro zone, saying it must take steps including "bringing down interest rates in the countries that are reforming and making sure those banking systems can provide the credit those economies need".

Obama, in a telephone call with French President Francois Hollande on Wednesday, August 1 "encouraged their efforts to take decisive action", the White House said.

Hollande reassured Obama that European Union member states aimed to enact soon the decisions taken at a summit in late June, according to the French leader's office.