UPDATE 2-Global Payments buys 51 pct of merchant JV with HSBC

(Adds comments from HSBC, Global Payments, shares)

LONDON, June 17 (Reuters) - U.S. electronic transaction firm Global Payments (GPN.N) has bought a 51 percent stake in a joint venture with Europe's biggest bank HSBC (HSBA.L) to provide payment processing services to merchants in Britain.

Atlanta-based Global Payments, which processes online credit card transactions, said it will pay HSBC $439 million in cash to acquire the majority stake in the joint venture.

Card processing handles transactions between merchants and a bank each time a credit or debit card is used. HSBC said it had wanted to grow its UK processing business and the deal with Global Payments will accelerate the plan.

Paul Garcia, CEO of Global Payments, told Reuters the joint venture is aiming to grow revenue by 15 percent a year. HSBC's UK merchant acquiring business reported revenue of $229 million last year.

By 1440 GMT Global Payments U.S.-listed shares were up 3.8 percent at $48.56. HSBC was up 1 percent in London.

HSBC currently processes card payments for UK merchants in 135,000 stores and outlets, giving it about a 14 percent market share. Garcia said he expects to win market share and will aggressively target mid- and small-sized merchants.

The transaction, which is expected to close within two months, will add to Global Payments' earnings in the first year following the close of the transaction, it said.

The new company will operate under the name HSBC Merchant Services.

The two companies already have a joint venture for card payments processing in Asia.

HSBC's 400 card processing staff will join Global Payments and no job cuts are expected, the bank said. (Reporting by Steve Slater in London and Supantha Mukherjee in Bangalore; Editing by Bernard Orr)