London  - British trade unions Thursday threatened a two-day strike over pay and conditions on London's busy Underground (Tube) network next month.

Members of the RMT Union voted overwhelmingly for strike action in their dispute with transport employers.

The 48-hour walk-out would take place from the evening of June 9 to the evening of June 11. London's Tube network is used by more than three million people each day. (dpa)