Low foreign savings interest - self assessment needed?

My wife lives and works in the UK. She is originally from Germany and still keeps her old German bank account and some savings in Euro. Part of it is kept in a savings account which occasionally generates interest in Euro (worth under £100 per year). Is it true that she wouldn't have to declare this as long as the total interest from savings (foreign and UK savings combined) are still under her allowance of £1000? Or would she need to do a self-assessment as soon as ANY foreign income is involved, no matter how low? Thanks.

Hi,

If your wife is UK resident and domiciled, the income still needs to be declared.

Thank you.