Abdul Razak Noorbhai, chairman of Al Jama-ah in Gauteng, claimed yesterday that a picket will be staged at the convention centre and there will be calls for Blair to be tried by the International Criminal Court for his role in the invasion of Iraq.

Al Jama-ah is a political party in local government but claims to have support from trade unions and faith-based organisations.

Blair will speak at Discovery Invest's Leadership Summit. Tickets cost in excess of R5700.

The National Prosecuting Authority is investigating an NGO's call for a "citizen's arrest" of Blair - for a financial reward.

The website www.arrestblair.org is pooling donations saying that the money will go to anyone who makes a public but peaceful arrest of Blair according to the guidelines on the site.

Other speakers at this year's "leadership summit" include Finance Minister Pravin Gordhan, chess champion Garry Kasparov and Archbishop Desmond Tutu.

According to Tahir Sema, spokesman for the SA Municipal Workers' Union, a letter is being drafted to Tutu to ask him not to speak at the summit.

Herschel Mayers, chief executive of Discovery Life, said yesterday that he was "a little surprised about the reaction" to Blair's appointment in Sandton.

"We're not saying that we support him or that we don't support him, but he is a prominent international leader and we are glad to have him speaking," said Mayers.