Those portrayed in the paintings include people from Laos, Cuba, the UK, Japan, China, Chile and Australia, who came from all walks of life, such as State leaders, astronauts, soldiers, politicians, writers and journalists.

"The paintings express Vietnam's deep gratitude to our international friends for their feelings, sacrifices and contributions to Vietnam during the fierce wars, as well as during the development process," said Vu Xuan Hong, chairman of the Vietnam Union of Friendship Associations.

The paintings will have more faces of friends added over time, he said.

Among the works displayed are a painting of Len Aldis, a British activist who joined mass demonstrations to protest the US invasion in the south of Viet Nam. In 1992, he established the UK-Viet Nam Friendship Association in the UK and conducted charitable activities in Vietnam.

There is also a painting of Raymond Aubrac (1914-2012), a French engineer who hosted President Ho Chi Minh in 1946 when the President visited Paris and helped Ho Chi Minh in his diplomatic activities. In later years, Aubrac travelled to the US many times to meet US Secretary of State H. Kissinger, General Secretary of the United Nations Kurt Waldheim and Pope Jean Paul VI to seek a solution to the war in Vietnam.

After the war, he persuaded US authorities to hand over maps showing where bombs and mines had been buried so Vietnamese authorities could defuse or remove these explosives.