A voting option allowing Hongkongers to veto all candidates in the 2017 chief executive election has gained more currency as a means to break the political deadlock after a top official said it "could be an option to consider". Secretary for Justice Rimsky Yuen Kwok-keung SC said yesterday that definitions of blank and invalid votes would need further clarification in the legal provisions to avoid confusion and potential court challenges. "The so-called blank vote could refer to those writing nothing on the ballots or those regarded as invalid votes in accordance to the existing laws, or it could also refer to adding a 'none of the above' option on top of the two or three candidates," he said. Yuen is the second key official, after Chief Secretary Carrie Lam Cheng Yuet-ngor, who has refused to rule out the idea ahead of the second round of consultation on reform, which is expected to begin this month. "From a purely legal perspective, the matter could be dealt with at the stage of local legislation … [and] be considered in future discussions," Yuen said. But he added any changes would need to consider the electoral system as a whole, including other elections in Hong Kong. The local legislation would come after the resolution to amend the electoral methods stipulated in the Basic Law obtained two-thirds approval - or 47 out of 70 lawmakers - in the Legislative Council. The "none of the above" idea has been floated by academics including Professor Albert Chen Hung-yee, of the University of Hong Kong, to ease the impasse over a stringent reform framework set by Beijing in August, under which a 1,200-strong committee dominated by Beijing loyalists would choose two or three candidates for a public election. Under existing electoral regulations, ballots in which a voter does not indicate a clear choice of candidate are considered invalid, but they do not affect the election result. But under Chen's proposal, a majority vote for the "none of the above option" or a majority blank vote would see the election declared invalid. However, the response was lukewarm from Emily Lau Wai-hing, chairwoman of the Democratic Party, who said the pan-democrats wanted a genuine choice of candidates rather than an option to veto all candidates. Hong Kong-based China watcher Johnny Lau Yui-siu and veteran democrat Dr Law Chi-kwong doubted Beijing would accept the idea, believing it had tightened its grip since Occupy Central and the pan-democrats' vow to boycott the consultation. Separately, a three-metre by 15-metre yellow banner reading "I want genuine universal suffrage" was unfurled near the top of 495-metre Lion Rock yesterday morning - and was swiftly removed by firefighters. It was the fourth time a banner has gone up at Lion Rock since October.