Withholding interest – double tax relief

Hello. Hope you are doing well.

I was reading an article online on tax and found the following;
“A UK company has to pay withholding tax of 20% on interest it pays to Non-UK Resident companies”

What does a withholding interest work like? Is it like tax deducted at source and reduces my corporation tax? Or is it just lost?

Thanking you in anticipation.
Best regards,
Pas Cave Dire