The Bharatiya Janata Party on Tuesday claimed the "climb-down" by the Left on the Indo-US nuclear accord was the result of a "trade-off" between the government and the CPI(M) over Nandigram and said the "compromise" has "exposed" the Marxist party's "drama" over opposition of the deal.

The saffron party said its "apprehension that the Left objection and opposition to the nuclear deal was not based on principle, but on convenience has ultimately come true" in the wake of the CPI(M)'s "compromise" with the government.

"The moment they got into political difficulties because of Nandigram they have come forward to compromise with the government on the deal and offered concessions," senior BJP leader Yashwant Sinha said.

His comments came after the Left appeared to have toned down its opposition, giving green signal for the government to begin talks with the IAEA on the deal.

Sinha alleged that there was a trade-off between the Congress-led government and ally CPI(M) that they will help each other on Nandigram and the nuclear deal and adoption of a "soft attitude" by the Left makes this understanding evident.

"The prime minister is silent on Nandigram, which the governor described as a war-zone. Had it been a non-UPA or non-Left ruling state, the government would have descended heavily on the state," he added.

Sinha said the BJP had all along been suspecting that the Left opposition to the deal was a "drama" the "last act" of which was played out on Tuesday. "The Left stand completely exposed today on the nuclear deal issue," he remarked.