His initiatives in administering the city of Taipei include changing the transliterations of street names and the line and stations of the Taipei Metro to Hanyu Pinyin, as opposed to Tongyong Pinyin. Ma has expressed mild support for Chinese reunification and opposition to Taiwan independence. He opposed the 2004 referendum, which had been widely criticized by the U.S. and PRC. Nevertheless, his opposition to the Anti-Secession Law of the People's Republic of China, while other leaders of his party remained silent on the issue, led to him being banned from visiting Hong Kong to make a public speaking tour in 2005. He also criticized the PRC for the Tian'anmen crackdown.