PASSENGERS will face disruption over seven consecutive days in a serious escalation of the rail strikes next week after informal talks to end the signal workers' dispute

collapsed yesterday in mutual

recrimination.

After the 24-hour strike which begins at noon today, the RMT transport union has called stoppages on three successive working days starting next week. Signal staff are to walk out on Friday, 12 August and the following Monday and Tuesday. The timing of the strikes means that passengers can expect disrupted services from the night of Thursday, 11 August to the morning of Wednesday 17 August.

The impact of future industrial action could be considerably worse than previous days of disruption. RMT leaders report that a majority of the 500 signal box supervisors, who help to provide services on strike days, have voted to join their subordinates in walkouts. The result of their ballot is due tomorrow, and both groups of employees could be on strike from 12 August.

British Rail hopes to provide more than one in three trains during the eighth signal workers stoppage today, continuing the improvement in services since the first stoppage on 15 June brought nearly the whole network to a halt. The two-month campaign of walkouts has lasted longer than any other period of industrial action since the rail network was nationalised in 1947.

An intensive programme of shuttle diplomacy by the conciliation service Acas ended in failure yesterday. Railtrack, the state-owned company which runs the industry's infrastructure, denounced the union's declared intention of negotiating as a 'sham' and RMT accused the management of engaging in a 'public relations exercise'.

Railtrack said last night that it had given ground during the informal conciliation process. As part of an 'interim' offer management originally proposed an 'unconsolidated' rise of 6 per cent which would not have applied to allowances and overtime rates.

This week management offered to 'consolidate' half of that, which would have meant a 3 per cent increase on additional payments.

Management also proposed that following the interim payment, which would be available only if the union agreed to the whole restructuring package, there would be negotiations to work out the details of the new work arrangements.

David Armstrong, personnel director at Railtrack, expressed 'deep disappointment' over the RMT's 'inflexibility'. He said: 'It is clear that the RMT's claim to be prepared to negotiate freely on the package is a sham. They have not made a single concession.'

The union said that an 'upfront' offer of 5.7 per cent on basic pay was made before the strikes began and withdrawn on the orders of John MacGregor, the Secretary of State for Transport at the time. To agree to the new deal would show 'stupidity rather then flexibility', said Vernon Hince, the RMT's chief negotiator.

In Railtrack's south-west region, management meets today over its plan to offer nearly pounds 800 to employees to break the strikes. At the weekend the company indicated that the money would be paid to those crossing picket lines today. Yesterday however the company said that the money may be available for those prepared to defy next week's strike. The union argued that the delay showed there were 'few takers'.