Paris officials have announced a crackdown on rats which blight parks and gardens around the City of Light and are thought to easily outnumber humans.

The city's rodents were given an image overhaul in 2007 in the hit animated film "Ratatouille" which depicted them cooking in a famous restaurant.

But they remain a health hazard and eyesore for Parisians as well as an embarrassment after pictures of them scavenging on the grass in front of the Louvre museum in 2014 made foreign newspapers.

"In order to stop the recent increase in the presence of rats around Paris, an immediate and targeted action plan has been put in place," Paris city hall announced on Wednesday.

Eradicating the vermin is "impossible", the statement said, but reducing their number "significantly" can be achieved by blocking exits from the sewer system, reducing their habitats and trapping them.

Around half a dozen squares and gardens have been temporarily closed and traps have been laid, with other areas set to follow including the park in front of the Eiffel Tower.

Other measures will include new rat-proof rubbish bins and efforts to ensure garbage or food is not left for long periods in the street.

Pest control experts estimate that there are around two rats for every one of the two million people who live in central Paris.