BANGKOK (Reuters) - Thailand’s foreign ministry on Tuesday said it would talk to more than a dozen foreign diplomats after the military government accused them of “breaching protocol” by witnessing a rising political star being charged with sedition.

The diplomats mainly from Western nations and two international organizations accompanied Future Forward Party leader Thanathorn Juangroongruangkit on Saturday when he reported to a Bangkok police station to face criminal charges.

The former auto parts tycoon was charged with sedition and other violations for allegedly providing assistance to anti-junta protesters in 2015. He said the charges are politically motivated, which the government denies.

“This is a matter concerning the Thai justice system and if we don’t have confidence in it and don’t follow our processes, then it could provide the opportunity for others to interfere,” Prime Minister Prayuth Chan-ocha told reporters.

Referring to the observers, Prayuth said, “I am not sure if they were real diplomats.”

Foreign diplomats have observed police and court proceedings against political activists since the 2014 coup, but Foreign Minister Don Pramudwinai said it broke diplomatic protocol and could been seen as interfering in the justice system.

“We have told ambassadors of each country before that this sort of action is inappropriate,” Don told reporters.

Foreign ministry spokeswoman Busadee Santipitaks told Reuters the diplomats would be invited to the ministry “to hear our explanation about the truth.”

Future Forward made a surprisingly strong showing in the March 24 election, coming in third with 6.2 million votes.

The party has joined an opposition “democratic front” alliance that will try to form a government and block Prayuth from staying in power. The final results of the election may not be known for weeks.

The sedition charge is the latest legal case against Thanathorn and the progressive, youth-oriented party he formed last year.

Piyabutr Saengkanokkul, the party’s secretary-general, received a police summons on Tuesday for an online statement he made about the dissolution of another anti-junta party in March.

Police have accused him of contempt of court and breaching computer crime law, which he denies.