PROTESTORS say they are planning to block the Prince of Wales bridge on Saturday.

Hundreds are expected to stage a protest on Saturday, September 30 in opposition to Wales' new 20mph default speed limit. 

Organisers say they are planning to either block the M4 bridge, or drive at 20mph from Aust Services near Thornbury to Cardiff Gate.

Earlier this month, Wales became the first nation in the UK to lower the default national speed limit on residential roads from 30mph to 20mph. 

An organiser said on Facebook: “20 is NOT plenty. 

“The community is coming together to fight the new 20mph speed restrictions!

“Let our voices be heard!

“We will meet at Magor, Aust services for the English supporting the welsh at 1pm convoy to the prince of wales bridge at a stand still in both directions at 2pm, police escorts/traffic wardens may be attending.

Gazette Series: A protest has been planned on Saturday to block the Prince of Wales bridge against the new 20mph limit in Wales A protest has been planned on Saturday to block the Prince of Wales bridge against the new 20mph limit in Wales (Image: Newsquest)

“Hard shoulder to remain unblocked for ambulances. 

“It will be a peaceful protest to stand together and fight the 20mph new speed restrictions, we’re getting up earlier for work because of those doing 10-15mph.

“The confusions of some signs have not been changed yet. Car clubs will be attending.

“Join us to let our voices be heard!"

According to the South Wales Argus, Gwent Police have been informed of the potential protest and are working to reduce its impact.

A petition against the 20mph rollout in Wales has been signed by more than 430,000 people.

The Welsh Government has said that cutting the speed limit would protect lives and save the NHS in Wales £92 million a year.