The plea was made by the NSEL Investor Forum when its members met Food and Consumer Affairs Minister K V Thomas.
"We have asked the minister to merge NSEL into FTIL the promoter and relatively stronger company," the forum's Chairman Sharad Kumar Saraf told reporters after the meeting.
There are around 13,000 investors including 7,000 small investors whose Rs 5,400 crore are stuck in the NSEL.
"Government has given power to FMC but that power is not used properly. Some strictness is required in that and there is a need to speed up the investigation, otherwise the money will be diverted elsewhere," Saraf said.
The government must speed up the inquiry otherwise this fiasco will adversely impact on the FII investments, he added.
Thomas ensured the forum that the government is looking into the matter and that he was also in touch with the Finance Minister, Saraf said.
NSEL, promoted by Jignesh Shah-headed FTIL, is facing a crisis after it suspended trade on July 31, raising concerns about possible default of Rs 5,600 crore owed by 24 buyers/ members.