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.
More top news
Three-quarters of Britons polled said they would support more sex and relationship education in schools.
The full list of winners of the 89th Academy Awards in Hollywood.
The Oscars was plunged into chaos as La La land was mistakenly announced as the best picture, the actual winner was Moonlight.