Rate of tax credit relief allowed: (optional)

Hello. I have earned interest in France on which I have been taxed 12.8% (I am a higher-rate tax payer) - Since i have already paid tax, it makes senses for me to claim tax relief, right? - I indicate the amount of tax deducted by the French authorities, so why do I also need to indicate the Rate of tax credit relief allowed? It says optional but doesn't let me leave the page if I don't chose something. - Should the rate I am made to chose not be 12.8%? Yet I can only select the rates proposed. Do I chose the closest one? Thanks for your help.

Hi ,
 

Please have a look at article 12 on interest is the UK / France tax treaty.  It advises that interest arising in France and beneficially owned by a UK resident, is taxable only in the UK.  With that being the case, you need to claim the tax back in France and cannot claim tax relief in the UK.  You will need to request a certificate of residence :  How to apply for a certificate of residence to claim tax relief abroad   which you should give to the French authorities, when claiming the tax back . Thank you .