Oilfield services company Schlumberger Ltd secured EU regulatory approval on Monday to buy Smith International in a $11.34 billion deal that will allow it to drill deeper for fossil fuel.

The acquisition, unveiled in February, was the latest in a string of oilfield services deals underlining the recovery in the sector.

"After examining the operation, the (European) Commission concluded that the transaction would not significantly impede effective competition in the European Economic Area (EEA) or any substantial part of it," the European Union executive said in a statement.