China's cancer-stricken Nobel laureate Liu Xiaobo is in critical condition. The hospital treating him said today that Liu's tumour has grown and his liver is bleeding.<br/><br/>China has come under international pressure to let its most prominent dissident go abroad, but Chinese doctors said that Liu is too sick to travel. But two foreign physicians, American oncology expert Joseph Herman from the University of Texas' MD Anderson Cancer Center and German doctor Markus Buchler of Heidelberg University, visited Liu on Saturday and said he could still leave the country.'Beijing has come under fire from human rights groups over its treatment of Liu.