"It has been decided to resume services at a speed of 80 kmph against the maximum permissible speed of 120 kmph," Urban Development minister Kamal Nath said in reply to a question.
He said the Delhi Airport Metro Express Private Limited (DAMEPL) had appointed Hong Kong Technical University for a detailed analysis of the damaged clips on the Airport Metro Express Corridor.
"The consultant has undertaken various measurements to find out the cause of the failure of the clips. No report has been submitted by the consultant about the findings," Nath said.
He said before suspension of the train services in July 2012, trains were running at 80 kmph on account of the problem of breakage of clips.