Major closures on the M25 and M26 start tonight... as part of an upgrade to the Kent and Surrey border.

The anti-clockwise section of the M25 will be shut between junctions 6 and 5 from 10pm to 6am for a new gantry and signs to be installed.

Diversions will run between the A22 and A25.

A temporary rolling road block may also be needed on the clockwise carriageway while the gantry is lifted into position.

The work is part of the scheme to increase capacity on the motorway between junction 5 for Sevenoaks and junctions 6/7 for Godstone and the M23.

As work continues, it will be necessary to close the Londonbound M26 between the M20 and the M25 at junction 5 on the following dates:

• Sunday September 22 between 10.30pm and 5.30am
• Monday September 23 to Wednesday September 25 between 10pm and 5.30am

Diversions will be in place via the A20 and M20 to the M25 junction 3.

Meanwhile, the clockwise entry slip road at junction 5, from the northbound A21, will be closed overnight, between 10.30pm and 5.30am, for two nights from next Tuesday.

Diversions will be set up via the M25 at junction 4.

Further overnight M25 carriageway closures for gantries to be installed are planned on the following dates:

• Saturday September 28: junctions 6 to 5 on the anti-clockwise carriageway
• Saturday October 5: junctions 6 to 5 on the anti-clockwise carriageway
• Saturday November 16: junctions 6 to 5 on the anti-clockwise carriageway
• Saturday November 23: junctions 6 to 5 on the anti-clockwise carriageway
• Saturday November 30: junctions 6 to 7 on the clockwise carriageway

Any future closures will be publicised in advance.