The United States and Canada said on Wednesday Europe must put up more of its own money to solve its sovereign debt crisis, clouding prospects that G20 talks in Mexico this week can lay the ground for a deal on bolstering IMF resources.

"We continue to believe that the IMF can play an important role in Europe, but only as a supplement to Europe's own efforts," a U.S. Treasury spokesperson said. "The IMF cannot substitute for a robust euro area firewall."

Group of 20 deputy officials are set to discuss boosting IMF resources, which will need leaders' signoff, at a meeting in Mexico City on Thursday and Friday ahead of a late February finance ministers' meeting of advanced and development nations.

The IMF currently has a lending capacity of about $380 billion and estimates there are about $1 trillion in "uncovered" financing needs over the next two years.