Spain's King Juan Carlos, patron of a wildlife charity, faced fire Monday for making an expensive hunting trip to Botswana while his country struggles with a recession.

Juan Carlos, 74, had urgent surgery on his hip after breaking it on the visit, which left him recovering in a Madrid hospital. But his condition was overshadowed by rare criticism of him for the reported hunting trip.

The palace would not confirm that Juan Carlos was on a hunting trip but did nothing to deny widespread media reports that he went to Botswana, a popular elephant-shooting destination, for a big-game hunt.

The Spanish branch of the WWF, which names him as honorary president, said Monday it "will make comments to the royal palace and reiterate its commitment to the conservation of elephants", in a Twitter message.

Leaders of the two main political parties refrained from explicitly criticising or defending the king, widely respected for helping steer the country to democracy after the death of dictator Francisco Franco in 1975.

But Tomas Gomez, leader of the Madrid branch of the opposition Spanish Socialist party, added his voice to criticism by various minority left-wing political groups and unusually strong censure by the mainstream media.

"The head of state must choose between his obligations and duty of service of his public responsibilities, and an abdication that would allow him to enjoy a different kind of life," Gomez told reporters on Sunday.

Right-leaning newspaper El Mundo called it "an irresponsible trip, made at the most inopportune moment", in an editorial on Sunday.

"The sight of a monarch hunting elephants in Africa when the economic crisis in our country is causing so many problems for Spaniards does not set a good example," it said.

A petition on the online forum Actuable listed 40,000 signatures urging the king to give up his presidency of the Spanish WWF.

Two other animal rights groups, Igualdad Animal and Equanimal, plan to demonstrate on Tuesday outside the hospital where the king is convalescing, they said in a joint statement.

Botswana authorities confirmed Monday that Juan Carlos fell and broke his hip during an elephant hunting expedition in the north of the country.

Juan Carlos arrived in the southern African country last week and left after his fall on Friday in the northern Okavango region, government spokesman Jeff Ramsay told AFP.

"He had a hunting permit for hunting elephant," said Ramsay. "My understanding is he slipped while in his chalet rather than in the bush."

A widely circulated picture of the Juan Carlos posing with an elephant was taken on a previous trip around 2005, Ramsay said.

Botswana has over 150,000 elephants, but the country issues few hunting permits.

"It's something the world doesn't understand. We don't know what to do with all of them, they are too many. We've tried giving them to other countries," said Ramsay.

Juan Carlos has suffered a troublesome few months marked by an embarrassing corruption scandal implicating his son-in-law, the Duke of Palma, Inaki Urdangarin.

Saturday's surgical operation was his fourth in two years.

His surgeon Angel Villamor said the king could expect to be discharged from hospital this week. The Hospital USP San Jose said in a statement Monday his condition "has developed very positively" and he was moving around.

Spanish newspapers published photographs taken in previous years of the king posing with a gun next to apparently dead elephants and buffalos.

In 2009 a court dropped charges against the three authors of a caricature that depicted Juan Carlos on a hunting trip in Russia where he allegedly shot dead a drunken circus bear.

One vocal animal rights activist, French former film starlet Brigitte Bardot, issued an open letter to the king, branding the hunting "indecent, revolting and unworthy of a person of your rank".

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