LONDON - The Archbishop of Canterbury has called the Church of England "deeply institutionally racist" and apologized for Britain's treatment of black people and other minorities since World War II.

Anglican clerics adopted a motion late on Tuesday seeking forgiveness from the so-called Windrush generation that moved to Britain from former Caribbean colonies since 1948.

The mass migration was promoted by the government to help rebuild the United Kingdom from the ruins of war.

Yet none received documents confirming their UK citizenship and the Caribbean countries' subsequent independence saw many denied basic rights.

Dozens were also wrongly deported in a scandal that rocked the government of former prime minister Theresa May.

Archbishop of Canterbury Justin Welby, the highest-ranking cleric in the Anglican communion, told the General Synod there was "no doubt" the Church of England was still "deeply institutionally racist."

"We did not do justice in the past, we do not do justice now, and unless we are radical and decisive in this area in the future, we will still be having this conversation in 20 years' time," the archbishop said.

"We have damaged the Church, we have damaged the image of God and most of all, we have damaged those we victimized."

The Times newspaper separately quoted him as saying: "I'm ashamed of my lack of urgent voice to the Church... It's shaming as well as shocking."

The resolution was adopted the same day as a last-minute court ruling kept 25 convicted foreign-born criminals from being deported to Jamaica.

Campaigners argued that Britain was sending back some people who came to Britain as young children and had no links to the Caribbean island state.

But Prime Minister Boris Johnson insisted on Tuesday that "these individuals should have taken the precaution of not being serious criminals."

The Court of Appeal ruled that 25 of the 50 people up for deportation had been denied proper legal advice because the phone signal in their Heathrow detention center did not work.

Eight of the 25 cases are now being reviewed by the Home Office after campaigners filed fresh legal appeals.