Thailand's foreign minister says he will summon representatives from the embassies of the European Union and the United States to discuss why he believes they breached diplomatic etiquette by observing a Thai politician being charged with sedition by police.

Foreign Minister Don Pramudwinai said Tuesday that foreign countries are barred from closely observing internal procedures "not only by etiquette but also by rules and regulations that the whole world abides by."

His remarks come after several countries sent envoys to a Bangkok police station last Saturday when Thanathorn Juangroongruangkit, leader of a popular new political party, was formally charged with sedition and other crimes following a complaint filed by a member of the country's ruling military junta.

Thanathorn had said that the accusations against him were politically motivated and expected.