Zimbabwean President Robert Mugabe has accused foreign mining companies of stealing the country's wealth, after an announcement that the government will take control of all diamond mines.

Mr Mugabe accused the companies of "swindling" and "smuggling" in an interview with state-run ZBC TV.

The 92-year-old leader denied that the move would affect relations with China, a major investor in the sector.

Zimbabwe was the world's eighth largest diamond exporter in 2014.

"We have not received much from the diamond industry at all," Mr Mugabe said, complaining that Zimbabwe had received $2bn (£1.4bn) from an estimated $15bn (£11bn) of revenues.

Mr Mugabe was also critical of Zimbabweans' role in the alleged theft, saying that those "expected to be our eyes and ears have not been able to see or hear what was going on".

Foreign mining companies can only operate in Zimbabwe as part of a joint-venture with local partners.

Last month companies operating in the Marange diamond fields were ordered to stop working after their licences expired.

Reports of abuse, including killings by the army, led to an international ban on diamond exports from Marange between 2009 and 2011.

Zimbabwe's economy has struggled since a government programme seized most white-owned farms in 2000, causing exports to tumble.