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Heart Breakfast with Jamie Theakston and Amanda Holden 6:30am - 10am
The Prime Minister's been telling London's Heart he's spoken to the Mayor about the idea of new laws to make it harder for tube staff to strike.
It comes after yesterday's 24 hour walkout in that row over job cuts.
Two more strikes are planned.
David Cameron also says getting rid of child benefits for higher earners was a very tough decision but is fair.