Avoid tax calculation for Unplanned delivery cost in MIRO

Dear experts,

I want to avoid tax being calculated on the unplanned delivery cost.

I know we can do that by posting the Unpl.del cost as separate line item. But, our scenario does not permit that. We have to distribute the Unpl.del cost to the invoice line items.

Is there a way we can acheive that? You help will be greatly appreciated.

Regards,

Vishal.