CAMP DAVID, Maryland — World leaders backed keeping Greece in the euro zone Saturday and vowed to take all steps necessary to combat financial turmoil while revitalizing a global economy increasingly threatened by Europe’s debt crisis.

A summit of the G8 leading industrialized nations came down solidly in favor of a push to balance European austerity — an approach long driven by German Chancellor Angela Merkel — with a dose of US-style stimulus seen as vital to healing ailing euro-zone economies.

“We commit to take all necessary steps to strengthen and reinvigorate our economies and combat financial stresses, recognizing that the right measures are not the same for each of us,” leaders said in a bold statement issued at their meeting at the Camp David presidential retreat in Maryland.

The message sent by the summit reflected his own concerns that the euro-zone contagion, which threatens the future of Europe’s 17-country single currency bloc, could hurt the fragile US recovery and his own re-election chances in November.

In their final economic communique, the Group of Eight leaders welcomed discussions in Europe to broaden the focus to more pro-growth remedies and said: “We reaffirm our interest in Greece remaining in the euro zone while respecting its commitments.”

It was unusual for the often-bland G8 communique to single out a relatively small nation. But fears that a political stalemate in Greece would lead to its departure from Europe’s monetary union at unknown costs to the financial system and global economic stability have spooked markets.

Spain too has roiled markets by revealing huge bad loans in its banking system as it struggles to rein in its budget while facing recession. “It is significant that a group as weighty as the G8 backs Greece and reinforces the idea that Europe needs a strong union. — Agencies