NEW DELHI, May 26: National security, national pride and the fact that all previous governments encouraged the nuclear programme are likely to be the pivots of the government's defence to the onslaught on the nuclear tests planned by the Opposition during the Budget session beginning tomorrow.Projecting itself as truly nationalistic but also peace-loving, the Bharatiya Janata Party-led government is expected to emphasise that it has taken a giant stride for India to occupy its rightful place under the sun.India did not want to be left behind when other countries were developing atomic energy, Prime Minister Atal Behari Vajpayee told his party MPs today.An indication of the government's line in Parliament was given by Vajpayee's address to the meeting of the BJP Parliamentary Party today. He said his government had decided to carry out the nuclear tests because it was felt that they were needed for national security.Vajpayee's address also contained pointers to the statement on the tests he isscheduled to make in both Houses of Parliament tomorrow. This will be followed by a two-day debate, at the end of which Vajpayee will give his reply.The PM also emphasised that the nuclear programme had been fully supported and encouraged by previous governments . The tests were ``not the result of a day's work'' but the ``culmination of relentless hard work pursued by the scientists and engineers'', he said.