BERLIN (AFP) -- German authorities demanded Wednesday that US Internet giant Google bolster its privacy protection measures before it offers pictures of German city streets on its popular Street View service.

Google, whose German operations are based in the northern city of Hamburg, currently sends photographs taken abroad to the United States to have people's faces and cars' licence plates blocked out.

But German data protection officials are concerned that privacy rights could be violated because Google employees have access to the unfiltered pictures.

"Raw data (featuring streets photographed by Google) are sent to the United States and we have no control over them," Hamburg's top data protection official Johannes Caspar, who has jurisdiction for all of Germany, told AFP.

Google began taking panorama photos of German streets last year using cars equipped with cameras but has not yet posted them on Street View, Caspar said.

Caspar said Google executives would meet with city officials next week to try to resolve the issue but said Germany reserved the right to stop Street View if the company fails to comply with its privacy guidelines.

Launched two years ago in the United States, Street View gives Google users a 360-degree view of any given street. In response to critics, Google says it blurs out the faces of any passers-by caught by its cameras.

Greece this month barred Google from taking any more photographs on the nation's streets for Street View until it disclosed how long it intends to keep the images and what steps it is taking to alert residents liable to be photographed of their privacy rights.