US Republican and Democratic leaders were working to resolve their differences and hammer out a Unanimous Consent agreement that will push the US-India civilian nuclear deal to the floor of the Senate for debate and vote during the current lame duck session.

"We are also continuing our efforts to reach an agreement for the consideration of the US-India Peaceful Atomic Energy Cooperation Act," Senate Majority Leader Bill Frist said in concluding remarks at the end of business day on Tuesday.

Although leaders of Republican and Democratic parties have said that they are keen on tabling the civilian nuclear deal in the Senate, they and senior staffers are still working on the broad parameters of how the bill will be debated and voted.

Though the bill has strong bi-partisan support, the point of disagreement is on the number of amendments that are to be offered to the legislation. Prior to the adjournment in September, the Republican Party had indicated that it was willing to accomodate as many as six amendments, but apparently the Democrats were insisting on three times that number.

Along with the final accord on the number of amendments, the Unanimous Consent agreement will also specify the length of overall debate for the bill with time to be equally split between parties as also the time limit on the discussion for each one of the amendments.

Senator Russel Feingold issued a statement on Tuesday saying that he will offer an amendment to ensure that American nuclear assistance to India is civilian in nature and will not be used to further develop the country's nuclear weapons capability.

The Wisconsin Democrat offered a similar amendment when the Senate Foreign Relations Committee was marking up the legislation.

That attempt was shot down solidly on a bipartisan basis with senior lawmakers making the point that amendments like this were "killer amendments" and could not be permitted.

Even critics of the US-India nuclear deal concede that the agreement will clear the Senate given the strong bipartisan support.

However, time will be a constraint given the hectic Senate schedule in the lame duck session, which comes after the Congressional elections that saw Democrats wresting control of Capitol Hill.

The Senate is expected to adjourn this week and return for business for two weeks in the first half of December.

If the bill on nuclear deal, aimed at allowing US to supply nuclear fuel and technology to India, is cleared by the Senate in its current session, it will then go back to the House and a single version will then be passed again by both the House and the Senate, before it reaches the president's desk.

The Senate has voted on the Military Construction and Veterans Affairs Appropriations and is scheduled to take up the Agriculture Appropriations Bill when it meets on Wednesday.

Indicating the difficulties the Indo-US civilian nuclear deal faces in the changed power balance in the Congress ahead of its lame duck session, two leading Democrat members on Tuesday pitched for a critical look at the agreement in view of proliferation concerns and New Delhi's support to Tehran's right to peaceful use of nuclear energy.

However, the refrain of both the Democrats are that the agreement should be in the best interests of US national security with one of them saying that 'trust, but verify' should be the guiding principle in approaching the bill.

One of the bitter critics of the deal in the House of Representatives Edward Markey alleged in a statement that it is clear that on the issue of preventing Iran from going nuclear and on the crucial issue of nonproliferation "India's record is not encouraging."

"Why has India repeatedly insisted that it is Iran's inalienable right to develop nuclear technologies? It should raise eyebrows all over the world to hear the Indian foreign minister say that India 'has and would continue to help Iran in its controversial bid to generate nuclear energy.'

"How can we even consider eviscerating our non-proliferation laws to send advanced nuclear technologies to India while they are playing defense for one of the world's most dangerous nuclear wannabes?" he added.

"I urge my colleagues in the Senate to investigate these issues thoroughly before they cast a single vote," Rep. Markey said.

The Massachussetts Democrat pointed to the Congressional Research Service report "India and Iran: WMD Proliferation Activities," that has said Washington has repeatedly sanctioned Indian companies and scientists for allegedly transferring WMD technologies and materials to Iran and other countries.

In 2004, sanctions were imposed on the chairman and the managing director of the Nuclear Power Corporation of India for nuclear-related transfers to Iran.

In July 2006, two Indian companies were sanctioned by the US for transfers of dangerous chemicals to Iran.

India agreed to provide Iran a 10-megawatt nuclear reactor in 1991. "While this deal was cancelled under US pressure, India reportedly trained Iranian nuclear engineers," Markey has pointed out.

The author of the CRS Report Sharon Squassoni has referred to the September 2006 joint statement on Iran's nuclear program released by the Non-Aligned Movement. India called nuclear research and development a "basic inalienable right" of Iran's, and said that nuclear "choices and decisions" of different countries "must be respected."

India has refused to join the international Proliferation Security Initiative, a coalition of more than 70 nations dedicated to intercepting shipments of WMD materials. India has said that it has "certain concerns regarding the PSI's legal implications."

Markey has drawn attention to the fact that the CRS Report speaks of an unclassified 2001 CIA report to Congress which called India a "secondary proliferator" who is "beginning to supply technology and expertise to other proliferators." Also called "secondary proliferators" were Iran, North Korea, and Pakistan.