Responding to the article, Boris Johnson said: "Grateful as I always am to Andy for career advice, I am backing David Cameron all the way."
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Outbreaks of rain and strengthening winds will affect southernmost parts of England and Wales today.
An earlier debate on the issue was suspended as an 'expression of support' following the Westminster terror attack.
Five people were killed and dozens more were injured after a car and knife attack in the capital on Wednesday afternoon.