Cricketer-turned-politician Navjot Singh Sidhu on Wednesday formally resigned from the BJP and said it was a "painful decision" for him."I hereby resign from the party membership of the Bharatiya Janata Party," Sidhu said in a tweet, in which he posted his hand-written letter to BJP national president Amit Shah. "Long association, painful decision.... my wife, children and party not alone Punjab. Punjab first, Punjab Punjabiat and every Punjbai must win," he wrote.Sidhu had on Thursday formally announced a new political front 'Awaaz-e-Punjab' saying that his fight was against the system and the leaders who had "ruined" Punjab. Earlier he has resigned as a nominated member of Rajya Sabha.