The union representing the majority of Tube drivers has said “productive” talks with TfL means it will not yet be joining the planned strike action scheduled for next week.

Three of the four unions have planned two 24-hour strikes next Tuesday and Thursday, as talks progress to find a resolution to the ongoing dispute over working conditions on the new Night Tube service and other issues.

Aslef could still join the RMT, TSSA and Unite on the picket lines on August 25 and August 27 if negotiations with London Underground break down, but the tone from the union is optimistic.

“We are in productive talks with LU,” said an Aslef spokesman.

“We started them last week and there are further talks this week. They postponed the rosters for the Night Tube, so we agreed to continue talks with them.”

While Aslef just represents train drivers, other unions’ disputes centre around Tube staff conditions including working patterns and the closure of ticket offices.

If it goes ahead, the strike action next week could threaten the Night Tube start date. A TfL spokesman said: “We are working towards September 12 for the delivery of Night Tube and are operationally ready, but, as we have always said, this cannot be at any cost.”