India's most populous state is running out of meat, as tens of thousands of meat sellers across Uttar Pradesh close in protest over a government crackdown on slaughterhouses operating without licences or adequate paperwork.

After the Hindu right-wing Bharatiya Janata Party came to power in Uttar Pradesh earlier this month on the back of a resounding electoral victory and named a Hindu priest-cum-politician as the state's chief minister, the government began cracking down on illegal slaughterhouses and meat shops.

The new chief minister, Yogi Adityanath, is a strong supporter of laws protecting cows, which are revered by devout Hindus, and has publicly opposed beef consumption.

The slaughter of cows and the consumption of beef are taboo for most Hindus. Their slaughter is barred by law in most Indian states, including Uttar Pradesh.

"All the illegal operations in slaughterhouses should end now," Adityanath said on Sunday at a rally in his hometown of Gorakhpur, where he is also the high priest of the Gorakhnath Math, a religious order based in eastern Uttar Pradesh.

"The majority of the slaughterhouses and meat shops are running without licences and government approval. I know, in the name of buffalo, cows are being slaughtered in many abattoirs. This should end."

So far, there have been no reports that any of the slaughterhouses shut down were selling cow meat instead of the usual water buffalo meat, which is permitted.

Uttar Pradesh, with a population of 204 million, is India's largest meat-producing state and has 41 licensed slaughterhouses.

Many more operate illegally by bribing local authorities, like thousands of small businesses in this corruption-plagued country.

Uttar Pradesh's government earns more than 110 billion rupees ($1.7bn) a year from the industry.

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"We know it is a money spinner industry for the government, but the party had promised to people in its election campaign to close down illegal slaughterhouses and meat shops," said Vijay Bahadur Pathak, the Bharatiya Janata Party's state general secretary.

"Money or no money, we will fulfil our poll promise."

'Unjustified'

Aquil Ahmad, a meat shop owner in Lucknow, the state capital, said that even though he has a licence, he has decided to close his shop in support of others in his fraternity.

Meanwhile, many meat shop owners are struggling to obtain the requisite paperwork.

Niaz Quereshi, an official with Quereshi Mahasabha, an association of meat sellers, called the government crackdown "unjustified".

He said government officials were harassing people trying to get licences and were asking for bribes.

"We are being sent from one table to another and from one room to another by clerks," he said. "They are harassing us."

As meat has disappeared from the markets, many restaurants have been forced to shut down or change the menu.

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Tundey Kababi, a 105-year-old kebab institution in Lucknow known for its delicately spiced buffalo meat fare, has had to pull its top-selling item from the menu.

"We are not getting an adequate supply of buffalo meat because of the crackdown on slaughterhouses," said Tundey Kababi's owner, Raees Ahmad.

"We are forced to sell kebabs made of chicken and mutton. Our customers are not happy, but we have no other option."

The crackdown has even hit the carnivores in the state's zoos.

Zoos in Lucknow and the neighbouring city of Kanpur have sent an urgent message to the state government saying the lions aren't keen on eating goat meat.

"Now we serve goat meat, but the animals are not eating it to their fill," said Nasim Zaidi, a veterinarian at a state-run hospital.

The government has received similar complaints from a lion safari park in Etawah, which is home to three grown lions and two cubs.

"Initially, the lions were fed goat and chicken meat, but I am told that they are not relishing that," said Dara Singh Chauhan, Uttar Pradesh's minister for forests.

"Arrangements have been made to transport buffalo meat from other areas of the state."