Shanghai - A Chinese dissident called yesterday on communist leaders to embrace political reform and reverse their verdict on the 1989 crackdown on pro- democracy demonstrators in Tiananmen Square. China has officially labelled the unrest as a counter-revolutionary rebellion that had to be put down to prevent chaos. In an open letter to China's Communist Party leaders, Mr Bao Ge (33) also urged them to adopt freedom of the press and multi-party democracy when they gather for their congress on Friday.