LAQUILA, Italy (Reuters) - Indian Prime Minister Manmohan Singh expressed his concern at Pakistans lack of progress in investigating those behind the Mumbai attacks in a meeting with US President Barack Obama, an Indian official said on Friday. Singh also discussed militancy in Pakistan and regional security in a series of bilateral meetings and talks with leaders of Germany, France, Russia and Australia on the sidelines of the G8 summit in Italy late on Thursday, officials said. Analysts say Singhs move could cast a shadow over a meeting of the Indian and Pakistani foreign secretaries in Egypt next week as the two nuclear-armed neighbours try to reduce tensions. Our concern at the lack of progress in investigating the attack was conveyed, said a senior government official who did not want to be identified. He (Singh) also discussed regional security. India suspended a peace process, begun in 2004, after the attacks by Islamist militants on its commercial hub, Mumbai, in November. The United States is keen for both countries to resume talks to ease tensions on Pakistans eastern border with India, so it can focus on fighting Taliban militants on its western border with Afghanistan. Singh and his Pakistani counterpart are also expected to meet in Egypt.