Yes you can. If you dealyed renewing it, there is a fine of £1000 - I know someone who has been fined! If you are stopped by the police it is accepted that these kind of things happen and you would just have to produce it when it is returned from the DVLA. They don't take very long to renew it in my experience - I kept a photocopy before I sent my off - but luckily it was not needed!!