Surah An-Naml (The Ants), Verse 71

وَیَقُوْلُوْنَ مَتٰی هٰذَا الْوَعْدُ اِنْ كُنْتُمْ صٰدِقِیْنَ ۟

Wa yaqooloona mataa haazal wa'du in kuntum saadiqeen

“They also say: "When will this promise (come to pass)? (Say) if ye are truthful."”

Quran 27:71 (Yusuf Ali Translation)