JOHANNESBURG (Reuters) -Shoprite Holdings, South Africa's biggest supermarket retailer, reported a 9.9% rise in half-year earnings on Tuesday, as both upmarket and discount customers stocked up on food during the festive season.

Shoprite, with more than 2,700 stores excluding OK Franchise across 10 African countries, said headline earnings per share from continuing operations rose to 662.3 cents in the 26 weeks ended December 29, up from 602.8 cents.

Group sales from continuing operations grew by 9.6% to 128.6 billion rand ($6.91 billion), as the retailer's core business, Supermarkets South Africa, achieved sales growth of 10.4%, with like-for-like sales growth of 6.1%.

The sales growth in Supermarkets South Africa was supported by strong volume growth as a result of across-the-board gains in customer visits, up 4.1% and average basket spend increase of 6.1%, Pieter Engelbrecht, the Group CEO said in a statement.

Shoprite's rest of Africa supermarkets business, which operates in nine countries, saw a 4.1% increase in sales.

It declared an interim dividend of 285 cents, up 6.7% from a year earlier.

($1 = 18.6185 rand)