LISBON (Reuters) - The Portuguese government is seeking to sell a 49 percent stake in Angolan diamond miner Sociedade Mineira de Lucapa, Publico newspaper said on Tuesday 4 August citing a senior official.

Angola is one of the world's top five diamond producers.

The stake is held by the Portuguese Entrepreneurship Society (SPE), which is 81 percent owned by the Portuguese government. Angola's state company Endiama controls the Lucapa mine via its 51 percent holding.

"It doesn't make sense keeping this stake in strategic terms. We are selling, regardless of the results," Publico quoted Portugal's Treasury and Finance Secretary Carlos Pina as saying.

Diamond firms in Angola are struggling to recover from a 75 percent drop in gem prices last year caused by the global economic downturn. The price slump prompted BHP Billiton, the world's biggest miner, to abandon its exploration projects in Angola.

Publico said SPE has been loss-making for the past two years, both in net and operating terms. Last year's net loss was 1.4 million euros and operating loss totalled 1 million euros.

Endiama said last month it expects to produce between 7 and 9 million carats of diamonds in 2009, compared with 8.9 million in 2008.