VATICAN CITY, Feb 16 - Former US Cardinal Theodore McCarrick has been expelled from the Roman Catholic priesthood after he was found guilty of sexual crimes against minors and adults, the Vatican said on Saturday.

Pope Francis has decided that the ruling, which followed an appeal by McCarrick, a power-broker as Archbishop of Washington, D.C. from 2001 to 2006, was now final.

A Vatican statement said his crimes were made more serious by "the aggravating factor of the abuse of power".

The 88-year-old, who in July became the first Roman Catholic prelate in nearly 100 years to lose the title of cardinal, has now become the highest profile church figure to be dismissed from the priesthood in modern times.

The decision comes as the Church continues to grapple with a decades-long sexual abuse crisis that has exposed how predator priests were moved from parish to parish instead of being defrocked or turned over to civilian authorities in countries across the globe.

With the ruling, Pope Francis appears to be sending a signal that even those in the highest echelons of the hierarchy will be held accountable.

The ruling, made by the Vatican's Congregation for the Doctrine of the Faith three days ago, was announced ahead of next week's meeting at the Vatican between the heads of national Catholic Churches to discuss the global abuse crisis.

Defrocking means McCarrick can no longer call himself a priest or celebrate the sacraments, although he would be allowed to administer to a person on the verge of death in an emergency.

The allegations against McCarrick, whose fall from grace stunned the US Church, date back decades to when he was still rising to the top of the hierarchy there.

McCarrick, who has been living in seclusion in a remote friary in Kansas, has responded publicly to only one of the allegations, saying he has "absolutely no recollection" of an alleged case of sexual abuse of a 16-year-old boy more than 50 years ago.

BishopAccountability.org, a US-based group which tracks abuse, said it was "meaningful punishment, and one which most abusive bishops have escaped" but years overdue.

"Once again, under the glare of negative publicity, Pope Francis is prodded to finally do the right thing," a statement said.

Reuters