By Daniel Schweimler BBC News, Buenos Aires

About 600 people turned up for the soup kitchen's opening

It is run by community groups and will serve simple Argentine food for free while all around diners eat at some of the city's most expensive restaurants.

Radical speeches were not exactly what developers had in mind when they moved in to renew the area several years ago.

Expensive restaurants and plush hotels now line the waterfront.

This, the former docks area, is where businessmen and tourists eat their lunch.

But this is also where radical activist Raul Castells has opened a community kitchen to feed, for free, the city's poor.

The site was donated by a businessman.

The small kiosk-type building opposite the Hilton Hotel is topped by a huge board with the words "we are fighting for an Argentina in which the dogs of the rich don't eat better than the children of the poor".

It will serve bread, stews and soups bought from donations.

Local restaurant owners are concerned but few are protesting loudly - at least not yet.

One said: "Why here? Poor people don't live here anymore."

But there are plenty of poor people in other parts of Buenos Aires, a short walk from Puerto Madero.