"Entry of all buses, including All India Tourist buses/ Contract Carriage buses/ State Transport Buses or holding any other kind of permit into Delhi from other states except CNG / Electric or BSVI diesel buses will be restricted as and when GRAP IV invokes. The above mentioned restrictions shall stand automatically applicable, as and when GRAP - IV is invoked from the date of issuance of this order in Delhi Gazette, and if the GRAP IV is revoked the said restrictions stand terminated automatically, no separate order will be issued," PTI quoted an official gazette notification as saying.