LONDON, Sept 29 (Reuters) - Merlin Entertainments, the British theme park operator fined this week for a rollercoaster crash, lowered its full-year core earnings margin forecast on Thursday due to weaker trading at its London attractions like the Madame Tussauds waxworks.
Merlin said its London sites, which include the London Dungeon, had not seen a boost from the weaker pound sparked by Britain's vote to leave the European Union.
Merlin said year-to-date revenue at its indoor sites in city centres and resorts, fell 0.4 percent on a like-for-like basis, offsetting stronger trading at its theme parks, resulting in 1.3 percent like-for-like growth for the group.
Chief Executive Nick Varney said trading across its estate was mixed in the year to Sept. 17, including the key summer trading months of July and August.
"Our Resort Theme Parks Operating Group is now showing year on year revenue growth, reflecting the ongoing recovery in trading at Alton Towers," he said on Thursday.
"(But) London in particular continues to suppress overall trading performance as we are yet to see any significant benefit from the depreciation of sterling."
Merlin, the world's second-biggest visitor attractions group behind Walt Disney, said the tough trading conditions would results in a core earnings margin for the year in the "mid thirties", a downgrade from its previous expectation of about 40 percent.
Trade at its Alton Towers park was hit by a rollercoaster crash in June 2015 that seriously injured five people. (Reporting by Paul Sandle; editing by Kate Holton)