Va. Code Ann. § 15.2-2624

Notwithstanding any other provision of law or any charter provision, the governing body is authorized and required to levy and collect annually, at the same time and in the same manner as other taxes of the locality are assessed, levied and collected, a tax upon all taxable property within the locality, over and above all other taxes, authorized or limited by law and without limitation as to rate or amount, sufficient to pay when due the principal of and premium, if any, and interest on any general obligation bonds of the locality issued under the provisions of this chapter to the extent other funds of the locality are not lawfully available and appropriated for such purpose.