Unite, one of three unions involved in Tube strikes which are due to begin next week, has pulled out of the industrial action as talks with Transport for London resume to try and avert the walkout.
The union, representing 600 Tube engineers and maintenance staff, had joined the action of RMT and Aslef Tube workers announced last week.
The two sides are due to meet again in talks overseen by Acas after "productive" meetings began on Friday, bringing the two sides together for the first time since November.
"Unite is suspending its three days of strike action this month and in February over pay and night working on the London Underground," said Unite national officer Hugh Roberts.
"This is to allow for further talks with the conciliation service Acas on these issues. We will approach these talks in a constructive fashion and urge London Underghround management to do the same."
The first of three strikes is due to take place from the evening of Tuesday 26 January, with further dates scheduled for February.