Unite teamed up with Unison, GMB and Prospect in a meeting with EDF this week to discuss altered working conditions for smart meter installers.
Around 70 members of Unite across Bexley Heath, Kent, and Canning Town downed tools at the beginning of January protesting changes which could affect 500 staff, including working hours and use of telematics.
A spokesman for Unite said: “We made no progress with the employer . The joint trade union position was that the matters must be negotiated; the employer position was that it would be consultation only, we therefore adjourned.
“If no negotiated agreement is reached, we will be proposing to the other trade unions that we take joint trade union strike action.”
Additional changes the union wishes to discuss are criminal record checks, use of cameras, random drug and alcohol testing, and depot closures.
A spokesman for EDF said: “We have nothing to add to previous statements at this time. We remain open, as always, to meeting employee representatives.”
The unions are preparing a joint written response to the meeting outlining their position on these issues.