David Cameron described travel disruption caused by the Underground strike in the capital as "unacceptable" on Twitter.
It's unacceptable that millions of people are having their lives disrupted by today's Tube strike in London.
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The decision represents something of a victory for the president who will now be able to enforce most of his controversial 90-day ban.
Cool in the north, warmer air to the south
Police have warned the drug, known locally as "pink champagne", could be deadly.