The Liberal Party leader yesterday challenged acting Chief Executive Donald Tsang Yam-kuen to express his views on the West Kowloon cultural hub and other key issues. James Tien Pei-chun, who last week ruled himself out of the chief executive race said: 'Mr Tsang has never expressed his stance on important policy issues, such as the single-developer approach in the West Kowloon project.' Speaking on an RTHK programme, Mr Tien also maintained his earlier criticism of Mr Tsang's role in overseeing the development of the site. In December, he launched a rare attack on Mr Tsang, saying he could be sticking to the single-developer option for the project in exchange for tycoons' support in a possible bid for chief executive. Mr Tsang, who is considered a frontrunner for the job, has yet to declare he will run. When asked whether he stood by his earlier comment, Mr Tien said: 'I don't think my view has changed.' But he added: 'The main issue now is that a few months ago, the single-developer approach was Mr Tung [Chee-hwa's] business, but now it is different ... he [Mr Tsang] has never told citizens of his views on important policy issues.' He said irrespective of whether Mr Tsang would win uncontested, he should outline his policy platforms. Mr Tien had appeared to be the only serious challenger to Mr Tsang. But he ruled himself out of the race on Wednesday after the results of an internal opinion poll showed Mr Tsang was 10 times more popular than he was and mainland officials told him that the chief secretary would be 'good' for the post. Mr Tien also said he hoped that more candidates would come forward to stand for the top post. He said he needed to discuss with fellow party members whether or not they would consider supporting the nomination of Democratic Party chairman Lee Wing-tat, who is understood not to have enough backing to nominate to run in the July 10 poll.