The Archbishop of Canterbury has said a second referendum may be necessary as he warned a no-deal Brexit would be a "political, practical and moral failure".

The Most Rev Justin Welby told the Lords that if Parliament fails to back a deal with Brussels it will have shown itself to be "unfit for the job".

He warned that a no-deal Brexit could hit the "poorest and most vulnerable" communities the hardest and said warnings about huge queues of lorries at Dover are not "Project Fear". He said that MPs have a"duty to build a compromise", even if it is "unwelcome to some".

"If not there will be, by default, a no deal Brexit," he said. "That outcome would be not only a political and practical failure, but a moral one equally as serious as ignoring the result of the referendum entirely.

"A second referendum is not my preference, but if Parliament fails in the task entrusted to it, then regrettably it may be required. This is about more than Brexit, and Parliament must not show itself unfit for the job."