Does IRC §871(i) (no tax on deposit interest for non-residents) apply to interest paid by the IRS on delayed refunds?

Internal Revenue Code §871(i)(3) basically says that "deposit interest" on a deposit in a US bank is not taxable for US non-resident aliens.

The IRS pays interest on delayed refunds and issues a 1099-INT, which would normally be taxable income for a US tax resident.

Is this interest taxable income for a US tax non-resident or is it considered non-taxable under §871(i)(3) similar to most other interest income reported on a 1099-INT.

EDIT: My understanding is that if a NRA received the refund on time and put it in a bank account, the interest would not be taxable. Hence, the "spirit of the law" should allow the same for interest payed by the IRS for a delayed refund, but I don’t see this clearly mentioned anywhere.