Germany's economy ministry approved the sale of utility RWE's oil and gas unit DEA to a Russian investor, despite tensions between Russia and the West over the Ukraine crisis.

The go-ahead announced yesterday removes the biggest hurdle for the 5.1 billion euro ($6.9 billion) sale, a major plank in RWE's struggle to reduce a debt burden of more than 30 billion euros.

As part of the deal, Russian tycoon Mikhail Fridman and his co-investors will get stakes in about 190 oil and gas licences or concessions in Europe, the Middle East and North Africa.

Relations between Russia and the West were already deteriorating over Ukraine, when the deal was announced in March.

Deputy Economy Minister Stefan Kapferer said the government found that the deal would not endanger Germany's energy supply and the buyer consortium's European Union base had also been a decisive factor.

The EU's antitrust watchdog has already given the green light but regulators in a few other countries, which RWE declined to name, have yet to give their approvals. DEA has operations in about a dozen countries, including Britain, Norway, Denmark and Egypt.

The German government could theoretically have used a clause in its foreign trade law that allows it to block takeover deals that threaten 'public safety and order', but it would have been an unprecedented move.

RWE, Germany's largest power producer, has earlier said it expected the deal to be finalised this year.-Reuters