UPDATE 2-Woolworths 'gets serious' about Africa

* To open 58 stores on continent by June 2014

* Forms JVs in Tanzania, Uganda

* Eyes oil-rich Angola, Nigeria for expansion (Adds executive's comment)

By Tiisetso Motsoeneng

JOHANNESBURG, Sept 9 (Reuters) - South Africa's Woolworths aims to more than double its presence on the fast-growing African continent over the next three years, an executive said on Friday, as the retailer looks to fend off new competition from Wal-Mart .

Woolworths, which sells clothing and high-end food, has 46 stores in 10 African countries outside of South Africa, its main market.

"We are now getting very serious about Africa expansion and we want to see a significant acceleration," said John Fraser, a Woolworths executive in charge of the company's international business.

"We are looking at moving from 46 stores to 104 by June 30, 2014."

Fraser said the retailer would spend up 120 million rand ($17 million) on the expansion drive.

Wal-Mart , the world's largest retailer, in June completed its $2.4 billion purchase of 51 percent of local discount retailer Massmart , giving the U.S. giant a platform for further African expansion.

Wal-Mart's entry is likely to put the squeeze on established African retailers, analysts have said.

Woolworths, whose clothing and upscale food products are similar to that of Britain's Marks and Spencer , follows rivals Shoprite and Pick n Pay in setting out African expansion plans in the wake of Wal-Mart's entry.

Woolworths said it regarded trading beyond South African borders as "a major opportunity" for growth.

"Consumer spending accounts for more than 60 percent of the African GDP and this will increase with the growth of the upper and middle-income groups," said Glenn Gilzean, Woolworths' director for retail operations.

The world's poorest continent is rapidly changing, thanks to rising incomes and a growing middle class. Africa's population is seen roughly doubling to 2 billion by 2050.

Woolworths said it had formed a joint venture in Tanzania and Uganda, and was planning to open three more stores in the two east African countries by the end of the financial year.

Woolworths, whose financial year runs from the beginning of July to the end of June, also said it intends opening stores in oil-rich countries such as Nigeria and Angola.

The retailer, whose expansion drive would be mainly through its clothing business, said it will focus on joint ventures with local partners in Africa, rather than its previous franchise model.

Shares in Woolworths, which have climbed about 40 percent this year, were 1 percent higher at 39 rand by 1507 GMT, against a 1.5 percent fall in the JSE All-share index .

($1 = 7.153 South African Rand) (Additional reporting by Helen Nyambura-Mwaura; Editing by David Dolan and David Hulmes)