"We will defend the secular and pluralistic basis of our democratic Republic," he said while replying to the debate on the Motion of Thanks to the President's address in both Houses of Parliament.
Hitting back at Leader of Opposition L K Advani, who headed the Home Ministry during the NDA rule, Singh said the UPA Government had a better track record on the issue of internal security.
"Let me assure him (Advani) that in terms of real hard work on the ground, our Government and our home ministry have a better track record to show than that of the previous Government," he said.
Singh said, "Even when we have had terrorist incidents like the ones we saw during the NDA rule, we have not had a breakdown of law and order and upsurge of communal violence of the type we saw in Gujarat. Compare the violence after the Godhra incident in Gujarat to the situation in Maharashtra after last year's Mumbai blasts".
In his exhaustive replies, Singh dwelt on the issue of water-sharing, problems confronting agriculture, Indo-Pak relations and other aspects of foreign policy.
He announced that a meeting of the National Development Council is being called specifically to discuss the problems of revitalising the agricultural sector.
In an apparent reference to the Cauvery row between Karnataka and Tamil Nadu, he asked all political parties to treat water as a national resource and not an issue, which should divide the people. "We should all work together in a spirit of national unity and harmony to resolve these issues".
Singh said India was looking forward to hosting the SAARC Summit early next month. "India seeks a neighbourhood of peace, prosperity and mutually beneficial economic and social development in our sub-continent," he stressed.
"We have not slackened in our efforts to promote peace and stability in the region despite obvious difficulties", he said but did not elaborate on what these were.
The prime minister hoped the SAARC Summit will be "...purposeful and productive," and contribute to the progress and welfare of all people of South Asia.
Observing that India has been working purposefully for all round improvement of its relations with Pakistan, he made a mention of "difficulties that arise."
"But I believe that the efforts that we have made are beginning to bring positive results. We need to establish long-lasting peace, friendship and amity between our two nations.
We will work resolutely in this direction."
Singh said he was sure that through the dialogue process, "we will be able to resolve all outstanding issues".
Noting that India's ties with Russia, the US, the European Union, China, Japan and the ASEAN nations have all grown in the last two years, he said "there is a growing realisation of the importance of India in world affairs".
"We are now seen as important credible partners in managing the evolving global, economic and political order," he said.
Turning to the problem of minorities, the Prime Minister said Sachar Committee has brought out the stark reality about the conditions of Muslim community in the country.
Noting that the government was designing targeted programmes for minority concentrated districts, he said, "we make no apology about it".
He said that there would be no need for such programmes in the long run as all communities catch up in their social indicators. "But given current disparities, it is imperative that we carry all sections along."
On the insurgency in Assam and ULFA, he said that he has always condemned violence and extremism in the northeastern state.
"We will never hesitate to sit down and talk to a fellow Indian, howsoever misguided he or she may be -- if such conversation can bring peace to our people," he said.
At the same time, he said that "we will never compromise on the unity and integrity of our country or allow those who kill innocent people to go unpunished".
On the problems of agriculture, he said the country needed a technological breakthrough to improve the productivity of dryland agriculture.