Relief for interest on existing joint mortgage

A deed of trust has been completed allocating rental income 99% to wife and 1% to husband who is a higher rate taxpayer. The property was formerly PPR purchased with a joint mortgage which is still outstanding. How is the mortgage interest allowed against the rental income? Is it 50% each or shared 99%/1% or something else? Thank you

Hi,
Please ref to our guidance using the link below:
UK property notes (2022)
Thankyou.

Sadly that doesn't appear to answer the question, at least ot for a non tax professional

Hi,
 

Thank you for your question.  If the property is owned jointly and you have made a declaration of beneficial interest showing a 99/1 split then we would expect the rental income and expenditure to reflect this when each of you are reporting your share to us.  This would include the mortgage interest relief as a 99/1 split . Thank you .