The Congress on Sunday kept up the suspense whether it would clarify by Monday to the Left parties on the issue of moving forward on the Indo-US nuclear deal as the deadline set by the key outside supporters nears its end.

"It is for senior leader Pranab Mukherjee to reply. He will reply in an appropriate manner," was what AICC media department chairperson Veerappa Moily said when asked whether the head of the UPA-Left joint mechanism on the nuclear deal would respond before the Left deadline.

The party leading the coalition had earlier rejected the July 7 deadline contending sovereign governments or political parties cannot be bound by ultimatums.

The party top brass, including Prime Minister Manmohan Singh [Images] and Party chief Sonia Gandhi [Images], had held detailed consultations soon after the Left ultimatum.

The AICC has been unfazed by the Left action and has been maintaining that the nuclear deal is in national interest. The Left has been demanding that the Prime Minister should make the position clear on the issue before he proceeds to Japan [Images] on the G-8 Summit on Monday.