A diplomatic or tactful remark — a polite, formulaic expression used for social niceties and smoothing relations (not necessarily reflecting true feelings).
『また機会があれば』というのは多くの場合、外交辞令だ。
The phrase 'perhaps another time' is often just a diplomatic remark.
会議でのその謝辞はほとんど外交辞令に過ぎなかった。
That expression of thanks at the meeting was mostly just diplomatic language.
外交辞令だからあまり深く考えないほうがいい。
Don't take it too seriously — it was just a diplomatic remark.