BT has halted day-to-day dealings with the 90,000 staff who are members of the Communication Workers Union (CWU).
According to a report in the 'Financial Times', the move is in retaliation for last month?s one-day strike action by London telephone engineers, over BT plans to axe 4,000 jobs.
The giant telco hopes the ultimatum will teach the union to control some of its more militant branches, of which London is one, according to the article.
It emerged that BT thought it had averted strike action after a series of talks with national officers from the union.
BT has also called for a review of its fundamental relationship with the union.
Last month the union accused BT of ?deliberate understaffing? and pressurising staff to work overtime to cover the people it plans to lay off.
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