"Europe has made decisions and now it is time for Europeans to ... move forward and actually implement it," IMF First Deputy Managing Director David Lipton told Reuters Insider on the sidelines of the annual central bank symposium in Jackson Hole, Wyoming.

"The markets have been comforted by what was decided this summer by the heads (of government) and more recently by what was announced by (European Central Bank) President (Mario) Draghi and spreads have come down," he noted. Draghi vowed last month to do "whatever it takes" to save the euro, and the ECB meets to review its policy options on September 6.

"I think a reversal of sentiment ... could turn this into a more acute situation and so it is important that Europe put one foot in front of the other and start carrying out the things that they have decided," he said.

The ECB is studying ways to intervene in the short-term bond market. But German ECB policymaker Joerg Asmussen said on Thursday the ECB should only buy sovereign bonds if the IMF was involved in setting the economic reform programs demanded in return.

Lipton agreed that there needed to be monitoring to ensure compliance with steps to improve the economic fundamentals of the countries being helped, which could be done either by the Europeans or the IMF.

"The Europeans need to decide how they wish to go forward. We certainly can play a role," he said, adding "We're open to respond to our members' request but we've not received any, and so for now, we are standing pat."

(Reporting by Alister Bull; Editing by Neil Stempleman)

• A Permanent Economic Emergency