Europe's effort to expand its bailout fund to 1 trillion euros ($1.3 trillion) is falling short, forcing renewed consideration of a role for the European Central Bank in insulating Spain and Italy from the debt crisis, two officials familiar with the discussions said.

Finance ministers are holding an initial discussion today on channeling ECB loans to cash-strapped euro nations through the International Monetary Fund, aiming to bring the central bank onto the front lines without violating its ban on direct lending to governments, said the people, who declined to be identified because the talks are at an early stage.

With renewed prodding from the U.S., European leaders are pondering a fifth “comprehensive” fix after an October blueprint failed to stop a widening rout in Italian markets or quell speculation that France will lose its top credit rating. Germany is pushing for governance changes at a summit next week that would tighten enforcement of budget rules, a move that might make it easier for the ECB to step in.