Randstad's slowing sales in Britain, U.S. hit shares

(Adds details on UK market, shares fall)

AMSTERDAM, July 26 (Reuters) - Randstad, the world's No. 2 staffing agency, on Tuesday reported 11 percent higher core earnings in the second quarter, but its shares fell more than 5 percent on concerns about stagnating sales in the United States and Britain.

Underlying earnings before interest, taxation and amortisation (EBITA) reached about 240 million euros ($264 million) in the latest period, compared with 215 million a year earlier, roughly in line with market expectations.

Analysts polled for Reuters had expected underlying EBITA of 237 million euros.

Randstad is the second largest staffing company globally by sales after Switzerland's Adecco (VTX: ADEN.VX - news) and ahead of ManpowerGroup (NYSE: MAN - news) of the United States.

In North America, Randstad's underlying sales were flat amid slowing demand for its services, Chief Financial Officer Robert Jan van de Kraats said in an interview.

In Britain, gross profit was down 2 percent and 'perm fees', paid when clients permanently hire an employee provided by Randstad, fell 5 percent year-on-year.

Van de Kraats said the British market was hurt by a slowdown in hiring in the financial sector and concerns that the construction market would be hit by the country's decision to leave the European Union.

Randstad's shares fell 5 percent in morning trading in Amsterdam and are down 19 percent since the Brexit vote last month.

Although Randstad only generates roughly 4 percent of revenue in Britain, there are concerns Brexit could hit economic growth in Europe and the wider labour market.

($1 = 0.9082 euros) (Reporting by Anthony Deutsch; Editing by Biju Dwarakanath and Mark Potter)