The Home Office says passport office staff are working "seven days a week" to deal with an increase in passport applications amid complaints of delays.
Home Office Minister James Brokenshire said the passport office had taken on additional staff earlier this year to deal with "unprecedented" demand.
He said: "Between January 1 and May 31 HMPO has received 3.3 million applications - 350,000 more than the same period last year, and the highest volume of applications received for this period over 12 years."
"As a result they have put in place a system of measures to deal with it and to see that people receive their passports in good time [...] customer service staff are working seven days a week to process the high numbers of applications."
The Home Office has outlined how people who are facing delays to their passport renewal can get it fast-tracked for free.
If you are worried about your passport application not being ready ahead of your holidays, there are a few options available to you.
Photos shown to ITV News appear to reveal the scale of the backlog at the Passport Office, amid staff claims of "blind panic".