[4] During World War II he was a member of the Yugoslav government in exile in London, holding the position of Minister of External Affairs from 1941 to 1943.

[5] Ninčić accompanied young King Peter II of Yugoslavia on a visit to the United States and Canada in June and July 1942 which generated good publicity for the "Yugoslav cause," but in practice the concern shown by the Roosevelt Administration amounted to no more than superficial benevolent attitude.

[7] The indictment of the British Foreign Office officials was even worse:[7] "an insufferable bore and a clumsy liar," "an extreme Serb," "an obscurantist and obstinate intriguer with a pro-German, pro-Italian past, a not very pleasant present, and [....] no future at all," "an evil old man," "garrilous[sic] and muddle-headed," "tortuous and hidebound."

In 2006 a court in Serbia rehabilitated Momčilo Ninčić to the same stature he held before the communist party and people of Yugoslavia won power and freedom in their anti-fascist struggle.

His daughter Olga married a Bosnian Muslim student activist, later Communist Yugoslav apparatchik, Avdo Humo, just before World War II[8] and stayed in occupied Sarajevo when her parents fled with the royal government to Britain in 1941.