Campaigners fighting to save a children's heart unit are hoping Health Secretary Jeremy Hunt will reverse the decision today.
Mr Hunt is expected to make a statement to the Commons on the results of a review into the decision to reorganise children's cardiac services across England into fewer, more specialised units.
This review was ordered by Mr Hunt following a wave of protest in Yorkshire over the plan to shut the centre at Leeds General Infirmary as well as ones at Glenfield Hospital in Leicester and the Royal Brompton in west London.
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The action comes on top of an emergency timetable which has seen hundreds of trains a day being axed.