Delays in awarding the contract to build the trains for the Government's Thameslink upgrade may have put the project in jeopardy, a public spending watchdog says.
The National Audit Office (NAO) says the delays cast doubt on the government's ability to deliver a major upgrade of the key rail route by the 2018 deadline.
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In a wide-ranging Peston on Sunday interview, he said Parliament security needs reviewing and the PM's counter-terror strategy is flawed.
The terror attack carried out by Khalid Masood at Westminster that left four people dead lasted less than two minutes say police.
Two knives were found at the scene in Islington, North London, and the suspects fled on foot before being arrested.