Livebookings has announced that it is the biggest restaurant reservations Web site in Europe, where it is 40 percent bigger than OpenTable. In fact, it says, OpenTable is struggling to achieve growth in Europe.

Competition between the two Web sites is heating up. Livebookings just won London’s Restaurant Week away from OpenTable, and the site reports that it processed more than one million restaurant diners globally in March—its biggest month ever.

During the same month, Livebookings also closed a round of funding of $10 million in investment from existing Livebookings shareholders, including Balderton Capital ;and Wellington Partners.

“The proceeds of the funding and record covers levels will help us to cement our leading position in Europe,” says Colin Tenwick, CEO of Livebookings. “Our 8,000 restaurant customers outnumber our nearest competitor by more than 40 percent and restaurant reservations have increased by a staggering 92 percent compared to March 2010.

“Successful initiatives such as Restaurant Weeks in Denmark and Sweden, run by our consumer brand Bookatable, have contributed to this exciting milestone. We are helping all the restaurants we work with improve their profit margins and fill their tables, and with this in mind we expect more success stories and continued growth in the future.”

Livebookings also beat out OpenTable for a two-year exclusive partnership deal with the London Restaurant Festival.