Police have been called to an incident at Westminster after a man was sighted on the roof of the House of Commons.

Officers were notified of the man on the roof at 9.15pm, however a police spokesman said they had no description of the individual or any information about why he had climbed the roof of the building.

A Scotland Yard spokesman said: "At 9.15pm officers were made aware of a man trespassing on the roof at the Palace of Westminster."

Sky News reports that there is no banner visible and nothing as yet to suggest that the incident is related to a protest by an organised group. The fire brigade and ambulance service are at the scene and a police boat is on the Thames.

The Houses of Parliament has been scaled by protestors in the past after being targeted by campaign groups, including those opposed to a third runway at Heathrow.

Dozens of Greenpeace protesters once climbed on to the roof to call for action on climate change and unfurled banners which read: "Change the politics, save the climate." A protest by the group was staged in Westminister earlier in the day.

The fire service said it had three crews on standby, but could not comment on any action being taken to gain access to the roof or apprehend the individual at this stage.