Jon Lamonte of Tube Lines says they have prepared contingency plans to keep the Underground moving during the strike. Some maintenance workers will walk out at 4pm this afternoon.
Tube Lines operations director Lee Jones said: "A strike on this issue is completely unnecessary and will not achieve anything.
"We urge the RMT leadership to end their strike threat and return to talks, as it will only be resolved through constructive discussion.
"The RMT's ballot showed that less than 44% of its members voted in favour of strike action. Any action would be by maintenance staff, not Tube drivers and station staff.
"Should a strike go ahead, we have plans in place which will enable London Underground to operate Tube services on all three lines and to minimise any disruption."