Mobile operator MTN's market cap is almost twice the size of East African nation Tanzania’s gross domestic product (GDP), an expert has said.

According to Dr Martyn Davies, chief executive officer of Frontier Advisory, the South African headquartered telecoms giant is one of Africa's ‘winning companies’.

Frontier Advisory is a research, strategy and investment advisory firm, and has advised a large number of multinational companies on their strategies in Africa and other emerging markets.

And speaking at the annual MasterCard Africa Knowledge Forum in Johannesburg South Africa this week, Davies listed his top eight companies that are winning on the continent and becoming Africa's multinational giants.

MTN is one of those companies that has fast adopted the multinational concept, Davies stated.

According to the World Bank East Africa's Tanzania had a GDP of $28.24 billion in 2012.

Meanwhile, ShareData Online indicates that MTN's market cap as of June 9 this year stands at $43.1 billion.

“We often talk about investing in countries but when you look at it would you rather invest in a country or company. African countries or African companies?

“These companies have created more value in the last decade or so than African countries have in half a century. A company like MTN is bigger than Tanzania,” said Davies.

"So will you put your money in Tanzania or MTN?" he asked.

MTN is Africa's largest mobile operator. The telco has operations in 22 countries on the continent, in Asia and the Middle East with over 200 million subscribers.

In Nigeria, MTN is the largest mobile operator with over 50 million subscribers in that country.

"When MTN went into Nigeria, analysts in this country (South Africa) actually sold their stock and said, that is too much risk," he said.

"In 2000 they were selling their stocks because they didn't understand the issue of first mover, capturing consumers, consolidating and building a long term business, Phuthuma entirely saw it."

“What they are today is probably one of the world's if not the leading mobile telecom company,” Davies stated.

Davies also noted that among the top eight winning African companies is South Africa’s multinational media firm, Naspers.

Around 2000 and 2001 Naspers invested $35 million in Chinese company Tencent. Today that investment is now worth $13 billion, Davies told the audience.