, the four GT categories are in mixed health. GT1 has been all but phased out with the removal of the class from the FIA GT1 World Championship and later the discontinuation of the series. GT2 is used by the American Le Mans Series, European Le Mans Series, FIA World Endurance Championship, Asian Le Mans Series, and the International GT Open. GT3, currently the most popular of the GT classes, is used by the FIA GT3 European Championship, Blancpain Endurance Series, and most national series such as ADAC GT Masters or the British GT Championship. GT4 has also been phased out like GT1 with the removal of the category from the Blancpain Endurance Series and the cancellation of the GT4 European Cup for 2012 due to issues regarding the organiser.