Traders in Port Talbot have set up a petition against the possible closures of the M4 junctions leading to their town.
Proposals have been made to close slip roads at junction 40 and 41 - two of the main entrances in and out of Port Talbot - for a six month trial over the summer months.
The Welsh Government says it is looking to reduce traffic congestion in the area, but no decisions have yet been made.
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