Foreign aid budget and asylum seekers

Can someone confirm or correct me on this.

As far as I can work out (and something I rant about on comment sections often so if it's wrong I need to know) the majority of the funding for housing asylum seekers comes from our foreign aid budget.

This is money that if we weren't spending it on hotels, we would be spending it abroad, on.. foreign aid. So effectively we are spending money in our own economy from our foreign aid budget. Hotels pay corporation tax, employ people who pay income tax, buy stock and items that all have VAT on them.

Am I wrong?

The numbers spent on housing asylum seekers are HUGE, no doubt. But without getting into a different argument, from what I understand we're actually subsiding the hotel industry from the foreign aid budget and giving ourselves extra tax receipts from money that was previously spent abroad.