First of all why congress is not asking BJP support? BJP and SS have already gone one step ahead in national interest that they are supporting the deal with small modifications. Now it is congress turn to put one step ahead. BJP doesnt want to be ashamed by unilateral suppoting the congress. Because Congress is always on their toes to humiliate BJP. So majority do not want this. Majority will not be happy if BJP is humiliated. Anyhow if Congress is not signing the deal BJP will sign after the next election. Congress is worried that they will loose minority vote if they ask BJP support.