The launch of the new "independent trade union federation" was delayed on Saturday as buses transporting delegates were stopped and searched by traffic officers, organisers said.

The trade union, co-ordinated by former Cosatu boss Willie Madisha, was meant to be launched at 9am at the Pretoria show grounds, but by 10am there were barely 50 people present at the venue.

Co-ordinator Siphiwe Mabaso said he had received information that buses transporting delegates from all over the country had been stopped by traffic officers and searched.

"They were taken off the road and searched... some of them are arriving now, but we may have to wait a while for others," he said.

Mabaso added that 1500 delegates were expected at the union launch and that Madisha was "on his way".

The union was formed as a result of workers' frustrations with large unions like Cosatu being attached to political parties.

Madisha told a press briefing earlier this month that workers had approached him to "help them" organise themselves into a new trade union due to his decade long experience with Cosatu, South Africa's largest trade union federation, and a prong in the ruling alliance.

The delegates present at the venue on Saturday morning expressed frustration at the late start. Many were sleeping in their cars on the lawn outside the auditorium.

Sapa