Indications of SP being open to doing business with the Congress was also evident in its attack on the BJP saying fundamentalism and communalism were a ‘bigger danger’ than the nuclear deal.

At the same time it said it couldn’t support the deal till Prime Minister Manmohan Singh comes out with a public statement allaying their misgivings.

After getting a special briefing from National Security Advisor M K Narayanan on the deal at an undisclosed location, SP leader Amar Singh told reporters that it was for the Prime Minister to decide how he would meet their concerns.

"What Narayanan told us is alright, but the Prime Minister should make a public statement in Parliament or outside and tell the nation publicly," he said adding the party had its apprehensions over the provisions of 123 agreement and the US Hyde Act.

SP chief Mulayam Singh Yadav's brother and Parliamentary Party leader Ram Gopal Yadav was also present during the briefing.

Singh said on the basis of the briefings they had from the Left parties earlier, the SP had some misgivings, which it had expressed in Parliament.

Narayanan was also asked about the anti-Iran vote cast by India in the IAEA, which it felt amounted to compromising India's sovereignty, he said.

Attacking BJP, Singh said that for SP communalism and fundamentalism were bigger enemies.

"More than the deal, we are worried about intentions of communal forces of turning UP into a laboratory of Hindu extremism. Keeping in the mind the sensitivities in view of the fact that Agra, Mathura, Kashi are in UP and the statement by a fundamentalist leader of the BJP that UP will become the next Gujarat, we do not want innocent Muslims to be killed like in Gujarat post Godhra," he said.

The party also took into account the declaration by L K Advani in Kanpur a few days ago that SP was the number one enemy of BJP in Uttar Pradesh, he said.

He said BJP leader Jaswant Singh came and met him on Wednesday and suggested that the Left parties, SP and BSP should along with BJP form a block and vote against the Government on the deal.

He also quoted the BJP leader as saying that the line of Left parties and the BJP was one and the same, but he added that the SP's line was different as it felt that communalism was a bigger danger.

"There is a world of difference between the ideologies of SP and BJP," he said adding that the SP had rejected the BJP's offer of a V P Singh-type experiment in 2007 under which Mulayam Singh Yadav would be made the Prime Minister with outside support from the BJP and Left parties.

Jaswant Singh also shared his experience of dealing with the US during his tenure as the Foreign Minister, Singh said.

He said the proposal conveyed through Jayalalithaa in hotel Maurya in return for election of Bhairon Singh Shekhawat as President was rejected by SP and other UNPA leaders Chandrababu Naidu, Farooq Abdullah and Om Prakash Chautala.

Tomorrow, he said, at the UNPA meeting the SP would brief leaders of other parties about the discussions with Narayanan.

"We are outside the Government, it is the Left which has been supporting the Government. Even when we went to offer our support to the UPA, it was the Left, Comrade Surjit who forcibly took us.

"Left parties even remained silent to whatever respect or disrespect was shown to us at the dinner of the Congress President," he said.

"Whatever they are saying, they are insiders, we are outsiders. They are part of the Government, they are kingmakers," he said.