Traffic wardens in Camden, central London, were set to begin an eight- day strike for higher pay on Wednesday of this week.
The Unison union members are demanding outsourcing giant NSL pays them £10.50 an hour, and better terms and conditions.
They had previously struck for four days from 2 September.
Workers across Barnet council in north London have called a strike during the Tory party conference against further privatisation.
The Unison members are set to walk out for 24 hours on Wednesday 7 October.The council is set to publish a report calling for slashing libraries on 2 October.