Image caption The new speed limit came into force on Sunday

A new 20 mph speed limit is operating in Belfast city centre.

The zone takes in May Street at the back of city hall, goes on as far as the Cathedral Quarter before going past the back of CastleCourt centre.

Roy Gordon, Transport Northern Ireland, said the new limit was part of a strategy to reduce the number and severity of collisions.

But he said commuters would not notice a significant increase in journey times.

Image caption Signs have been placed along the zone indicating the new speed limits

"The longest length of this zone is 700 metres and the difference between driving that at 30 mph and 20 mph is just over 20 seconds," he told BBC Northern Ireland's Good Morning Ulster on Monday.

"The zone is where we have the largest number of pedestrians and largest number of cyclists.

Image caption The new limits cover the main pedestrian zones within the city centre

"We have kept it relatively compact. It covers the main pedestrian zone and and front and back of city hall."

Mr Gordon said this was a pilot scheme - one of four across Northern Ireland.

"We will see how successful it is and take it from there," he said.

Drivers should keep a look out for new signage which has been put in place to mark out the new limits.