As a showdown over the Royal Institute of British Architects' (Riba) anti-Israel position moves ever closer, a resolution to the issue drifts further into the distance.

Revelations in the past month have offered hope and despair to Israeli architects who are threatened with removal from their international union, and their supporters in Britain.

Even Abe Hayeem, chairman of the Architects and Planners for Justice in Palestine group and a key supporter of Riba's position, reportedly described the situation as a "running disaster".

The sides - including the pro-and anti-Israel architects and Riba itself - are locked in a game of brinkmanship that should come to a head at next Thursday's Riba council meeting.

Since the original motion calling on the international union to suspend Israelis was adopted in March, Riba president Stephen Hodder has held secret meetings with Jewish architects and community leaders. He also met Yitzhak Lipovetsky-Lir, former president of the Israeli Association of United Architects (IAUA).

While insiders knew that there had been appeals to Mr Hodder to overturn the position, it was Mr Lipovetsky-Lir's decision to speak to this newspaper about his meeting in London last month that blew the lid off the behind-the-scenes lobbying.

Embarrassed by the Israeli's claims that Riba would reverse its position, Mr Hodder told the Building Online architecture news website: "The motion can't be overturned … it becomes Riba policy. We can't reverse the motion, whatever the Jewish Chronicle says."

There was further pressure this week, with Jewish property guru Sir John Ritblat and his wife Jill - both Riba honorary fellows - telling the institute not to become "an engine for political manipulation or bias". Renowned Israeli architect Moshe Safdie spoke at Riba last week, voiced his opposition to the motion, and dined with Mr Hodder. Such interventions are unlikely to make much difference.

One Jewish architect with inside knowledge of the private talks said Mr Lipovetsky-Lir's claims had "weakened the strength of our hand".

To all of this add the fact that Albert Dubler, president of the International Union of Architects (UIA), has told Riba that the union's global conference in South Africa in August would not debate the matter.

A potential disaster in Durban remains a real possibility for the Israelis and their supporters.