Protesting Nortel workers were forcibly removed from a central London hotel last week after picketing a channel partner event to demand an explanation for their treatment at the hands of administrators.
Nortel's PartnerFocus roadshow "seeks to connect our senior sales leaders with our most important and valued channel partners and resellers", the firm said.
At the end of March, Nortel made 228 positions in the UK redundant, spread across its Belfast, Harlow and Maidenhead facilities.
Those affected claim that Ernst & Young gave them minutes notice to clear their desks; offered neither a 90 day consultation period nor 90 day's pay in lieu; and did not make redundancy payments.
Nortel administrators Ernst and Young have refused a request for comment but claim they acted within the law.
Nortel will go no further than saying it has had to make some "difficult decisions" and claims it appreciates that "some of those decisions have had a very direct and personal impact on employees in the UK".
Meanwhile, SDLP MP Alasdair McDonnell has taken part in private discussions with Gordon Brown over the legality of the Nortel job cuts in Northern Ireland.
"We want to know why, despite repeated public assurances given by Ernst & Young when Nortel went into administration that it would be 'business as usual', promises that contracts would be honoured have been broken," he said in a statement.
McDonnell continued: "We want to know why Ernst & Young clearly failed to comply with the minimum consultation period of 30 days with employees. And we want to know why Ernst & Young agreed to pay a £15.5m bonus package for Nortel executives and then took a decision 10 days later to make 228 employees redundant at no notice with no redundancy pay."
More Nortel jobs are expected to be cut in Belfast in the near future, according to the Belfast Telegraph.
Terry Collins, regional industrial organiser for Unite, told the newspaper that 400 or so remaining staff were "very concerned" for their futures.
"They are wondering will they be treated the same as the 87 that were made redundant? I wouldn't hold out much hope that they would get more than statutory payments," he said.