US President Barack Obama has told Iraqis it is time for them to take reponsibility for their own country so US troops can leave.Speaking to Iraqi Prime Minister Nouri al-Maliki while on a surprise final stop on his long overseas tour, Obama voiced concern that elections later this year could bring unresolved political issues to a head. Experts fear recent security gains could unravel if Iraq’s factions fail to compromise on vital issues. Earlier, American forces gave their Commander-in-Chief a rapturous welcome at the Camp Victory military base. The President told them the next 18 months would be critical for their mission. He was referring to the August 2010 deadline for the withdrawal of all US combat troops from Iraq. Meanwhile, an Iraqi reporter jailed for hurling his shoes at former US President George W. Bush has had his sentence cut to one year from three. Muntazer al-Zaidi shot to instant global fame in December when he targeted Bush, who was deeply unpopular in Iraq.