BRUSSELS (Reuters) - EU competition regulators temporarily approved on Thursday an extra 10 billion euros ($12.50 billion) of funding guarantees for Dexia and said they would widen a probe to include this new state aid granted to the Franco-Belgian banking group.

The European Commission said its approval was valid until September 30 and that it had doubts that the extra funding guarantee comply with EU state aid rules.

"(The Commission) will take a final decision on its compatibility with EU state aid rules when it has finalized its assessment of Dexia's resolution plan," the EU executive said in a statement.

($1 = 0.8001 euros)

(Reporting by Foo Yun Chee, editing by Ben Deighton)