Vodafone Group paid â‚¬573 million (US$900 million) for a 70% stake in Ghana Telecom, the African country's third largest mobile phone operator, a Reuters report said.
The deal, signed in the Ghanaian capital of Accra, still requires approval of the country's parliament, the report added.
Vodafone spokesman Simon Gordon was also quoted saying it was expected to be given by the end of the third quarter of 2008.
Vodafone, the world's largest mobile phone group by revenue, said the government of Ghana would retain a 30% stake in Ghana Telecom, which has an enterprise value of around â‚¬637 million (US$1.3 billion).
'Ghana is one of the most attractive markets in Africa with mobile subscribers growing at more than 55% (per annum) and mobile penetration around 35%,' Vodafone CEO Arun Sarin said in a statement.
A government official said the deal would benefit consumers.
Vodafone said mobile penetration was low at 35 % in Ghana, which has a population of 24 million with more than 50% under the age of 25. About 2.7 million subscribers were added in 2007.
The deal gives Vodafone majority control of the company, which has a 17% share of the market and had around 1.4 million customers at the end of March. It is also Ghana's leading fixed-line operator.