The parties involved should exercise (self -) restraint and prevent the situation from getting worse.

有关各方应采取克制态度，防止事态扩大。

《新英汉大辞典》

The parties involved should exercise (self -) restraint and prevent the situation from getting worse.

有关各方应采取克制态度，防止事态扩大。

《新英汉大辞典》