The proceedings, which were supposed to be completed by Jan. 18, are now scheduled to continue until a still undetermined date, according to a spokesman for the mediation.
The discussions are being led by Ontario Chief Justice Warren Winkler, who will attempt to settle claims against the former telecom manufacturing giant by creditors in Canada, the United States and around the world.
The complex process currently involves about 100 interested parties, including Nortel pensioners, disabled former employees, bond holders, trade creditors and governments.
This will be the third effort to mediate settlements.
Last week, three former Nortel executives were acquitted of fraud charges nearly a decade after being accused of falsifiying financial records at the beleaguered company.