Deputy Prime Minister Prawit Wongsuwon has urged the Election Commission (EC) to look into whether the Future Forward Party has broken any laws.

Speaking after the Future Forward Party's general assembly at Thammasat University's Rangsit campus on Sunday, party founder Thanathorn Juangroongruangkit said he would pardon all political prisoners if the party gains power next February, when the election is due to take place.

Piyabutr Saengkanokkul, who was named secretary-general, insisted the party would seek to "amend" Section 279 of the charter on its first day in parliament.

This section legalises all of the orders, announcements and actions of the NCPO.

Mr Thanathorn was quoted by some media outlets as saying he planned to "tear the charter up" when he discussed the party's agenda. Deputy party leader-elect Chamnan Chanruang said this was just "rhetoric" and only meant rewriting the charter.

"The remark was used to promote the party and to gain people's attention. But tearing up the constitution cannot be done. The EC is working on this issue," said the deputy prime minister.

"Floating a political amnesty plan was another remark. We must let the EC look into whether this is right or wrong. I think he [Mr Thanathorn] was campaigning in advance [of the election]."

According to rules laid out by the National Council for Peace and Order (NCPO), political activities are still banned except for general assembly on a case-by-case basis.

Asked whether legal action would be taken against the NCPO in the future, Gen Prawit said, "What has the NCPO done wrong? It has done nothing wrong. Whatever we do, the prime minister orders scrutiny including budget approval and performance. We cannot do what we want but have to consider the law. The NCPO always follows the law," he insisted.

Future Forward Party secretary-general-elect Piyabutr Saengkanokkul asked in a Facebook post on Wednesday why the military could seize political power but the people could not rewrite the charter.

Meanwhile, former Democrat Party deputy leader Issara Somchai said Mr Thanathorn's remark was a careless one delivered for the benefit of his audience.

"The audience was satisfied but whether they understand the meaning is another story. The current constitution was passed in a national referendum which means the majority of the people accept it. The speaker did not recognise the will of the majority of the people who voted for it during the referendum," Mr Issara said, though he added that he understood the new party's need to garner support.

Mr Issara was a member of the now-defunct People's Democratic Reform Committee which staged street protests before the NCPO seized power in May 2014.