UPDATE 1-EU opens in-depth probe of proposed OMV/MOL deal

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BRUSSELS, March 6 (Reuters) - The European Commission said on Thursday it had launched an in-depth investigation of Austrian oil and gas group OMV's (OMVV.VI: Quote, Profile, Research) 14 billion euro ($21.5 billion) intended bid for Hungarian peer MOL MOLB.BU.

The European Union's top competition regulator set a new deadline of July 22 for its review of the proposed transaction, which would combine two integrated oil and gas companies operating in central and eastern Europe.

"This takeover would affect several strategically important energy markets," EU Competition Commissioner Neelie Kroes said in a statement.

"It is therefore crucial that the Commission makes sure that effective competition will be preserved for the benefit of both domestic and industrial consumers."

The Commission said the in-depth review did not prejudge the outcome of the proposed transaction.

OMV first revealed its takeover plans in summer 2007, but as yet has made no bid. MOL has fought the proposed acquisition since the beginning.

The Commission said it would look at the effects of the proposed takeover on the markets for refined oil products and natural gas.

In particular, the EU executive wants to know what would happen to the markets for refined oil products -- wholesale and retail -- if OMV took sole control of the companies' refineries.