There maybe many Billions of pounds in HMRC's bank account of unmatched funds that have built up over the decades.

There is no official figures (and so it cannot be verified by AI) for the amount being held but some sources state the amount maybe as high as £30 Billion.

Apparently their are rules that prevent offset, so if there are substantial funds the law/rules needs to change to allow HMRC to use the balances to pay down the National Debt and reduce interest charges paid.