Head of the Nobel Prize-winning UN panel on climate change, Rajendra Pachauri, on Saturday backed Prime Minister Manmohan Singh's push for the nuclear deal with the United States, saying it will help ease energy constraints for the power-starved country. In an interview, a day after the UNPCC won the Nobel Peace Prize along with former US Vice President Al Gore, Pachauri said that he hoped the nuclear deal with the United States would materialise.