Airport full-body scanners that show people's private parts are a virtual strip search, European Union lawmakers said on Thursday, calling for detailed study of the technology before it is used.

The scanners "have a serious impact on the fundamental rights of citizens", the lawmakers said in a resolution adopted by 361 votes to 16, with 181 abstentions.

The non-binding resolution asks the bloc's executive European Commission to carry out an economic, medical and human rights assessment of the impact of using full-body scanners.

The Commission proposed last month that the scanners be added to a list of security measures that can be used at airports in the 27-country bloc.

A number of EU states including the Netherlands already use body scanners, the Commission said, adding that it wanted to harmonise the conditions in which they can be operated.

The European Parliament resolution does not call for an outright ban on such scanners, but some EU lawmakers said they found them unacceptable.

"I think this is an offence against human dignity. Using this technology does not make us safer," said the leader of the assembly's Socialist group, Martin Schulz.

"These are machines that allow for you to be seen totally naked," Schulz said.

European Commission spokesman Jens Mester said fears concerning the EU executive's proposal were exaggerated.

"It is correct the body will indeed be pictured," he said. "But the quality is more that of a negative of a photograph, it is not a very clear image but sufficient to detect metal things, explosives or strange objects."