Archbishop Óscar Romero, who was killed in 1980 while he was celebrating Mass in El Salvador, will be declared a saint, Pope Francis has announced.
Pope Paul VI, who oversaw many of the reforms the Catholic Church underwent in the 1960s, will also be made a saint, the Vatican said.
A statement said that Pope Francis signed decrees on Tuesday giving the green light for their canonisation.
Óscar Romero is revered in his native El Salvador for denouncing repression.
Champion of the poor
Archbishop Romero was beatified in May 2015 in a ceremony in El Salvador which drew huge crowds.
The archbishop spoke out against the repression many of his compatriots suffered at the start of El Salvador's civil war, which lasted from 1980 to 1992.
When the US-backed Salvadorean army was using death squads and torture to stop leftist revolutionaries from seizing power, he used what would become his last homily to speak out against it.
"The law of God which says thou shalt not kill must come before any human order to kill. It is high time you recovered your conscience," he said, calling on the National Guard and police to stop the violence.
"I implore you, I beg you, I order you in the name of God: Stop the repression."
One day later, on 24 March 1980, Archbishop Romero was shot dead by a sniper as he celebrated Mass in a hospital chapel.
No one has ever been prosecuted for his murder but it is widely believed a right-wing death squad was behind it.
He has been an inspiration to many in Latin America who saw him as a champion of the poor and the oppressed but is still considered by some conservative and right-wing critics as a subversive.
Making Mass accessible
Pope Paul VI, who was born Giovanni Battista Montini in the Lombardy region of Italy in 1897, was beatified in 2014.
Elected pope in 1963, he continued the reforms of his predecessor, John XXIII, until his death in 1978. The reforms, brought in by the Second Vatican Council or Vatican II, changed the relationship between the Catholic faithful and priests.
Mass, which had been celebrated in Latin, was translated into the language of the congregation and priests faced church goers instead of the altar.
During his 15-year pontificate, Pope Paul VI wrote seven encyclicals.
One of them, Humanae Vitae (Of Human Life), published in 1968, was highly controversial due to its opposition to birth control and led to protests around the Catholic world.