Politicians who have turned to leaders in Beijing for their views on the national security bill have undermined the 'one country, two systems' framework governing Hong Kong, political commentators and some legislators said. They were commenting after Liberal Party chairman and executive councillor James Tien Pei-chun discussed with central government officials the special administrative region's biggest political crisis, triggered by Tuesday's 500,000-strong march. Mr Tien, who returned from Beijing yesterday, urged the government to postpone presentation of the bill to the Legislative Council for second and third readings on Wednesday. David Li Kwok-po, Legco's banking sector representative, will also go to Beijing today to discuss the issue, and it is believed Eric Li Ka-cheung, the legislator for the accountancy functional constituency, has also gone to Beijing for talks. Democratic Party chairman Yeung Sum said Hong Kong's autonomy had been compromised. 'Hong Kong should implement Article 23 on its own. If Mr Tung has opinions, he has to make his views known in Legco, not [have] someone go to Beijing [to discuss it].' Mr Tien said Mr Tung supported his trip to Beijing. Non-affiliated legislator Ng Leung-sing also said the implementation of Article 23 was a matter for Hong Kong. Political commentator Johnny Lau Yui-siu said: 'The 'two systems' has been destroyed by those people who have channels to communicate with the central government.' He said the central government would always exert influence when important issues arose, such as the reinterpretation of the Basic Law in 1999. Shiu Sin-por, executive director of the One Country Two Systems Research Institute in Hong Kong, said Hong Kong could enact laws on its own, but should be acceptable to the Beijing authorities.