"In my opinion, the Constitution is unfair to forbid political office holders from running businesses or having shares," he said in reference to Thaksin's controversial involvement in the Shin Corp sell-off.

Bhokin said the ban on equity stakes was unrealistic and impractical to enforce, arguing that Singaporean ministers were allowed to possess shares while serving in office.

With regard to the formation of a charter-drafting panel, he said his party wanted a broad representation in the rewriting process.

The drafting should involve various professional groups registered with the National Economic and Social Advisory Council and non-partisan experts, including former charter writers, judges and representatives from independent organisations, he said.

In one of its key recommendations, the ruling party suggested the formation of an election court to deal with penalties for campaign violations, instead of the Election Commission, he said.