Consider the following statements about the procedure of the amendment of the Constitution as laid down in Article 368:

1. A bill for amendment can be introduced either by a minister or by a private member with prior permission of the President.

2. Each House of the Parliament must pass the bill separately and in case of a disagreement between the two Houses, there is no provision for holding a joint sitting.

3. President can neither withhold his assent to the bill nor return the bill for reconsideration, to the Parliament.

Which of the above statements are correct?