Former U.S. House of Representatives Speaker Nancy Pelosi underwent a successful hip replacement surgery in Luxembourg on Saturday and is "well on the mend," her office said in a statement.

Pelosi, 84, was injured on a trip to Luxembourg and was admitted to a hospital for evaluation, her office said on Friday.

She was in Europe with a bipartisan congressional delegation to mark the 80th anniversary of the Battle of the Bulge in the Second World War.

"Speaker Pelosi is grateful to U.S. military staff at Landstuhl Regional Medical Center at Landstuhl Army Base and medical staff at Hospital Kirchberg in Luxembourg for their excellent care and kindness," her spokesperson Ian Krager said in a statement released Saturday.

Pelosi was the first woman to serve as Speaker of the House and had also been a longtime leader of the House Democratic Caucus.