Aug 27 (Reuters) - JD.com ( JD ) said on Tuesday its

board has approved a new $5 billion share repurchase program,

effective September, allowing the Chinese e-commerce giant to

buy back its stock over the next 36 months.

U.S.-listed shares of the company jumped 5.1% in premarket

trading.

JD.com ( JD ) is staring at stiff competition in the Chinese

e-commerce sector, with all major companies ramping up

promotions and discounts to woo cash-strapped consumers amid

muted recovery in the world's second-largest economy.

Earlier this month, big-box retailer Walmart ( WMT ) sold

its entire roughly $3.7 billion stake in JD.com ( JD ), ending an

eight-year investment in the company as it was yielding waning

returns.