Latvian Prime Minister Aigars Kalvitis said the ruling New Time party needed to change its tone after a meeting on April 3.
"It is difficult to work out pragmatic positions with hotheads," Kalvitis said.
Kalvitis said Economics Minister Krisjanis Karins, a New Party member, would have to step down if the current criminal investigation on the ministry's use of EU funds proved current corruption allegations true.
"I acted in accordance with the law and the approved procedure," Karins said.