NEW DELHI  - Indian Prime Minister Manmohan Singh left Monday for the G8 summit, where he is expected to tell US President George W. Bush that he will move ahead on a stalled bilateral nuclear energy deal. The Indian premier is among more than a dozen non-G8 leaders travelling to Japan where the world's richest nations are meeting, and his trip follows US pressure to advance the atomic energy pact before Bush ends his US presidency. Singh and Bush in 2005 unveiled an agreement to share civilian nuclear technology - a deal that when finalised would see India entering the fold of global nuclear commerce after being shut out for decades. But the Indian ruling coalition's leftist allies have been trying to derail the deal, vowing to bring down the government if the pact is implemented. A four-member bloc of communist parties, who have 59 seats in the 545-member parliament, insist the deal would bind India too closely to the United States, and have threatened repeatedly to force early elections if it moves forward. In a pre-departure statement, Singh confirmed his meeting with Bush but made no direct reference to the controversial issue. "I will present India's perspective on a wide range of global issues, including the state of the world economy, development, trade, transfer of technology, energy security and food security," he said. "I will, in particular, highlight the impact of the sharp rise in fuel prices on the global economy and the need for joint action by both (oil) producing and consuming nations." After months of stalemate, frantic politicking last week saw Singh's ruling Congress party successfully woo its onetime arch-rival Samajwadi Party (SP), which holds 39 seats, into backing the deal. Such bargaining appears to have helped Singh's Congress party to outmanoeuvre the left, and to stave off elections ahead of the scheduled May 2009 date. Parties from the left are insisting the government tell them on Monday whether it plans to head to the International Atomic Energy Agency (IAEA) to finalise a safeguards agreement " the next step in the process. But with its new partners on board, the Congress has scoffed at the ultimatum. The United States meanwhile has been pressing India to move on the deal before the end of Bush's tenure, warning that the pact may not survive in its current form under the next administration. The nuclear deal would allow India to buy atomic power plants and other technology despite not having signed international non-proliferation pacts. Singh argues the pact is crucial for India's energy security. But the leftist parties say the deal undermines the country's traditional status as a figurehead in the non-aligned movement. They also believe that allowing UN inspections of the civil nuclear programme " as demanded by the Americans " would harm India's strategic weapons programme. Before the deal is voted on by the US Congress, New Delhi also needs to earn a waiver from the 45-nation Nuclear Suppliers Group. The next key date in what is now beginning to look like the nuclear deal endgame will come Wednesday, when Singh will meet one-on-one with Bush in Tokyo, according to the Indian foreign ministry. The Group of Eight " Britain, Canada, France, Germany, Italy, Japan, Russia and the United States " is meeting for three days this week at the mountain resort of Toyako, in northern Japan. The G8 leaders are being joined by those of 15 other countries including India, China, Brazil, Australia and eight African states.