The Passport Office chief executive Paul Pugh said the agency was facing a challenging situation the like of which has not been seen in recent years, after apologising for the delays.
He said the Passport Office is dealing with 480,000 applications. Around 90% are being processed within targeted time.
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Former Girls Aloud singer Kimberley Walsh is pregnant with her second child, she has revealed.
Chancellor George Osborne will seek to reassure financial markets on Monday morning following Britain's decision to leave the EU.
In his first outing since the referendum result, the lead Leave campaigner has outlined his vision for a post-Brexit Britain.