Chief Secretary to the Treasury Danny Alexander said the £25 billion investment from insurance companies into British infrastructure projects was a "massive vote of confidence".
Speaking at the construction site of National Grid's London Power Tunnels, Mr Alexander said the investment was "more evidence we are rebuilding Britain."
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Tobias Ellwood ran towards gunfire to give mouth-to-mouth resuscitation to Pc Keith Palmer after he was stabbed by Khalid Masood.
The terror attack carried out by Khalid Masood at Westminster that left four people dead lasted less than two minutes say police.