For your question, we would like to answer as follow:

When you renew your driving licence, your UK passport is needed because your driving licence application processing will be faster: 

  •  In case you are 70 years or over, your UK passport is not always needed. However, your application process will be faster if you provide us with your passport. 

  • In case you exchange your paper driving licence for a photocard licence, sometimes your application is accepted but sometimes it is not. Please provide your passport number to make sure your application is accepted. 

  • In case you renew your driving licence(10 years replacement) or replace a lost, stolen, damaged or destroyed driving licence, your passport number is compulsory. If you do not provide your passport number, your application cannot be processed