St Mary's Cathedral is the principal church of the Roman Catholic Archdiocese of San Francisco

A church in San Francisco has promised to remove controversial sprinklers it installed to deter rough sleepers.

After an outcry, the city's archdiocese admitted it had been "ill-conceived" for St Mary's Cathedral to treat homeless people in this way.

The water system was put in place two years ago for safety reasons, it said, to stop needles and excrement being left in alcoves near the back door.

The sprinklers may also have been illegal, a church statement said.

"We have also now learned that the system in the first place required a permit and may violate San Francisco water-use laws, and the work to remove this system has already started, and will be completed by the end of the day," it said on Tuesday.

The archdiocese said it prided itself on its work with the homeless and the people affected had been informed before the sprinklers were installed.

"The idea was not to remove those persons, but to encourage them to relocate to other areas of the cathedral, which are protected and safer.

"We are sorry that our intentions have been misunderstood and recognise that the method used was ill-conceived."