BEIJING, Nov 9 (Reuters) - Supporters of China's disgraced senior politician Bo Xilai, who has been jailed for corruption, have set up a political party, two separate sources said, in defiance of a decades-old de facto ban on new political parties.

The Zhi Xian Party, literally "the constitution is the supreme authority" party, was formed on Nov. 6, three days before the opening of a key meeting of top Communist Party leaders to discuss much-needed economic reforms, the sources said.

It named Bo as "chairman for life", Wang Zheng, one of the party's founders and an associate professor of international trade at the Beijing Institute of Economics and Management, told Reuters by telephone.

"This is not illegal under Chinese law. It is legal and reasonable," Wang said, declining to say how many members the new party has.

A second source, who asked not to be identified but who has direct knowledge of the party's founding, confirmed the news.

Calls to the Communist Party's propaganda department seeking comment went unanswered.

China's constitution guarantees freedom of association, along with freedom of speech and assembly, but all are banned in practice. It does not explicitly allow or ban the establishment of political parties.

Bo, once a rising star in China's leadership circles who had cultivated a following through his populist, quasi-Maoist policies, was jailed for life in September on charges of corruption and abuse of power after a dramatic fall from grace that shook the Communist Party. (Reporting by Benjamin Kang Lim and Ben Blanchard; Editing by Neil Fullick)