The participation of an Israeli expert on conflict resolution at an NHS-sponsored event next week in Manchester was cancelled following pressure from local representatives of the UNISON trade union whose members were supposed to participate in the workshop.

Moti Cristal, a veteran Israeli adviser and trainer on negotiating skills, was scheduled to present a "master-class" on the Role of Negotiation in Dealing with Conflict at a seminar on conflict resolution for managers at NHS' Manchester Mental Health and Social Care Trust and UNISON officials on May 8.

On Friday, Mr Cristal received an email from the company organising the seminar, with which he has worked in the past, telling him that his lecture had been canceled "on the grounds that it is [the union's] policy and also that of the Trades Union Council to support the Palestinian people."

Kevin Nelson, the regional secretary of UNISON North West Region confirmed that "UNISON's local representatives at the Manchester Mental Health & Social Care Trust did request that the decision to invite Mr Moti Cristal to facilitate a Partnership Workshop on 8th May 2012 be reversed."

Explaining the decision, Mr Nelson said: "It was considered that the decision to invite a prominent Israeli negotiator would be unacceptable given UNISON and TUC policy on the Middle East conflict, the irrelevance of the speaker to working relationships within a local NHS Trust and the inappropriateness of funding an international speaker at times of such austerity, when front line staff in the trust are at risk of redundancy."

Mr Cristal has lectured to groups in Britain before on a number of occasions including a session with the Muslim Council of Great Britain (MCB) and has advised also human-rights organisations and Palestinian groups.

In response to the decision to cancel his lecture, he wrote to the chief executive of the Manchester Mental Health Trust, Jackie Daniel, saying that "in terms of your future bargaining position with UNISON, I believe that the last minute cancelation is perceived more of an appeasement toward UNISON, rather than a leadership call.

"Values-wise, unlike you, I am confident that the only way to resolve conflicts, let alone the Israeli-Palestinian one, is through effective communication and constructive dialogue, rather than violence or boycotts." He said that since the decision had been political, he was waiving his cancellation fee. A spokesman for the trust said no letter had been received from Mr Cristal.

Amir Ofek, the press attaché at the Israeli Embassy in London, said that "the cancellation of a private expert simply due to his citizenship or ethnic identity is a racist policy in every way.

"What is even more shameful is the fact this was supposed to be an NHS-sponsored workshop dealing, ironically, with negotiating and conflict resolution. It seems that those who canceled it are in urgent need of such training."

The NHS did not respond to requests for comments.