The mountain section of the TT course is due to close this morning (Saturday), as the one-way system which will operate during the festival is set up.

The road is scheduled to close from Barrule Park in Ramsey through to Creg-ny-Baa at 10am, and reopen later in the day allowing southbound traffic only.

The Department of Transport says the one-way system will be in place until June 15.

There's also a reminder that the mountain section will close earlier than the rest of the course before racing and practicing during TT fortnight, to allow signs and traffic cones to be removed.

The closure will be an hour earlier before practices, and 30 minutes earlier before races.