Bob Crow in talks to form a transport super-union

A new super-union could give workers even more power to take on Tube and rail bosses, it was revealed today.

RMT leader Bob Crow described as "historic" talks to merge his RMT union with transport union TSSA. The RMT has 80,000 members and the TSSA more than 28,000.

It would unite the RMT's blue collar staff, such as train drivers and engineers, with the TSSA's white collar membership which includes signal workers and supervisors.

Mr Crow said: "These talks will bring together two unions each with over a hundreds years of specialising in the transport industry."

Gerry Doherty, TSSA general secretary, added: "We owe an obligation to our children and our children's children to leave better organisations that protect workers in the very uncertain future that they currently face."

And in a direct appeal to Aslef, the powerful but smaller train drivers' union, Mr Crow invited "other specialist unions in transport" to joins the discussions at a future date.

The move has sent a shiver through City Hall, Tube bosses and the rail industry who fear increased strike threats in the run-up to the Olympics.

Network Rail, for instance, has agreed a ground-breaking two-year 10 per cent-plus pay increase - and up to £500 for working on Olympic Games services - for mainly RMT members.

TSSA staff, however, are only getting 2.5 per cent in a one-year deal. The union has begun a strike ballot with the result due next month. A walkout would threaten rail services over the bank holiday weekend.