From 1975, Souvanna Phouma lived in exile in Paris, France.
Prince Mangkra was the founder and president of the Laos Committee for the Defense of Laws and People, which aims to remove the current government of Laos and establish a constitutional monarchy.
Prince Mangkra Souvanna Phouma also served as a member of the Council of Regency of Laos.
He believed that the Laotian royal family can provide social and economic change for the Lao people to bring unity and bring a peaceful solution to problems faced by the country.
[citation needed] Prince Mangkra died on 8 January 2025, at the age of 86.