international scale
Refers to the scope, size, or level of something being international, often used in contexts like events, cooperation, or problems.
This problem needs to be tackled on an international scale.
An international-scale conference will be held next month.
国際的 is an adjective meaning 'international' in a general sense, while 国際規模 specifically emphasizes the scale or scope being international.
Compound of 国際 (international) and 規模 (scale, scope).