In a major decision, the Supreme Court on Wednesday said no vehicles which are BS-IV emission non-compliant will be sold in the country after April 1.Banning the sale of BS-IV non-compliant vehicles, the bench of Justice Madan B. Lokur and Justice Deepak Gupta said all the vehicle-registering authorities are prohibited from registering BS-IV non-compliant vehicles from April 1.However, the court said that if proof is furnished that the vehicle was purchased before April 1, then it will be allowed to be registered.