July 30 - Gap Inc is stepping up an expansion in Italy after initial store openings last year exceeded its expectations, the apparel retailer said on Friday.

The Portobello Road collection

Gap is opening a store in the main shopping district of Rome on Via del Corso on Saturday.

The company said it would open another four Gap and Banana Republic stores in Italy this year. It is also opening outlet stores in the country.

Gap's U.S. business is struggling to grow, so the company is expanding overseas and online.

The first Gap and Banana Republic stores in Italy opened in Milan in November. Within a few months, they were among the company's top performers globally, Gap noted on Friday.

Stephen Sunnucks, president of Gap's international business, said the Milan launch had exceeded the company's forecasts, "underscoring the potential for our brands in Italy."

Gap shares were down 0.7 percent at $19.38 in midday trading.

The stock is down about 14 percent so far this year. It slumped earlier in 2011 after the company slashed its profit forecast, partly because of higher cotton costs.

(Reporting by Alistair Barr; Editing by Lisa Von Ahn)