The ATP tour has fined Nick Kyrgios 15,000 euros ($A23,500) for inappropriate behaviour during the Queen’s Club tournament.

Kyrgios was caught on camera performing an imitation of a lewd act as he sat in a courtside chair at the change of ends during his semifinal loss to Marin Cilic on Saturday.

During an earlier win at the same tournament over Kyle Edmund, British broadcaster BBC apologised to viewers after a string of expletives by Kyrgios were audible on air.

The 23-year-old Kyrgios has won four titles on the ATP Tour and is widely considered to be a talented and temperamental player, but has a history of sanctions for his behaviour on and off the court.