The Duke and Duchess of Cambridge have played mother and father to a group of orphaned baby elephants and rhinos during a tour of one of the world's most important wildlife parks.

Armed with large bottles of milk, William and Kate fed the hungry animals who were impatient to get their meal and bellowed when they first saw rangers approaching with the flasks.

The Duke and Duchess were visiting Kaziranga National Park, home to elephants, water buffalo, the endangered swamp deer, tigers and two-thirds of the world's population of Indian one-horned rhinoceroses.

The park in the state of Assam in the north east of India is a unique mix of grasslands, wetlands and forest. It measures more than 800,000 square kilometres and is designated a Unesco World Heritage Site.

Earlier the Cambridges had a two-hour jeep safari into the heart of Kaziranga and gave a rhino a wide birth when they found it blocking their path.

They joked with village elders during a visit to a community in the park that two-year-old Prince George was "too naughty" to bring to India and would be running around.

Kate also said that seeing the local children, especially the young girl dancers, had reminded her how much she missed her own daughter Princess Charlotte, who is one next month.

William, who is a passionate conservationist, and Kate were introduced to the young animals at the Centre for Wildlife Rehabilitation and Conservation (CWRC).

It provides emergency care and rehabilitation for wild animals that have been injured, displaced or orphaned.

In a large area of grassland and sparse woodland the baby animals had gathered under the shade of a tree waiting for the royal couple who walked towards them.

The parental instincts of the Cambridges - who decided not to bring their two children on their seven-day tour of India and Bhutan - came to the fore during the encounter.

William and Kate fed all the animals in turn, crouching over the tiniest of the group - two female elephants and a rhino - to make sure they got every drop of milk, and also turning their attention to the older ones.

They were fed a milk formula every few hours with added coconut oil as a supplement.

Among the youngest was elephant Murphuli, who was just four weeks old when she was found in a tea garden trench in October last year.

The centre's vets hoped a female who rushed forward and examined the infant with her trunk was the mother but she was found in the same spot the next day.

Buree was another orphan elephant found, aged two months, a few days after Murphuli when she was rescued by villagers from a rocky pit, and after recovering from a swollen hip she is making friends with the other animals.

But it was Dunga the rhino, the smallest and newest resident at the centre, who won Kate's heart. The youngster was found alone by forest staff on patrol and when they failed to locate the mother he was taken to the centre.

As the couple fed the elephants some stretched out their trunks towards the bottles and all tipped their heads back to get every drop.

William and Kate gave the animals comforting rubs as they fed them, scratching the tops of their heads and patting their trunks.

Vivek Menon, chief executive officer of the Wildlife Trust of India which established the CWRC with a number other bodies, joined the royal couple for the encounter with the animals.

He said: "They were absolutely thrilled and loved being with the animals. The Duchess loved the baby rhino particularly.

"The Duke said if he could he would have spent the whole day there."

William and Kate began their day with an early-morning jeep safari in Kaziranga, with the Duchess casually dressed in a cream RM Williams blouse and brown Zara biker stretch pants.

After their encounter with the rhino, the press left the royal couple to enjoy a private excursion, during which they came across a herd of elephants.

Kate later changed into a Topshop dress for the visit to the community in Panbari where elders who gathered at the village's "Nam-ghar" or community centre could not resist asking, through a translator, why they had not brought their children.

Kate apparently replied: "Because George is too naughty. He would be running all over the place. The next time we come we will definitely bring them."

And seeing the young village girls left her pining for her own daughter.

The couple heard that the village was established in the 1970s after homes on nearby Majuli Island, one of the biggest river islands in the world, were flooded through erosion and the changing course of the river.

The flooding had the knock-on effect of causing the local elephant population to seek out higher ground, which resulted in them trampling through the community's paddy fields to get there.

This forced the village to diversify, and it now grows tea rather than rice because the elephants bypass tea plantations as there is no water to drink.

The Duke asked: "How do the local people view the elephants and rhinos - are they considered sacred?"

They were told the villagers "love" the elephants because they are happy to live alongside them.

William and Kate were reminded of their children again when they were that told painted models of baby elephants would be sent to them, when they visited the Kaziranga Discovery Park. It was built by Elephant Family, the charity founded by Mark Shand, the late brother of the Duchess of Cornwall, to help safeguard the Asian elephant.

They were met by Ruth Powys, Mr Shand's former partner and the chief executive of the organisation.

"The first thing they said after we introduced ourselves was how sorry they were about Mark," said Ms Powys, who showed the couple around the new centre which is still under construction.

She added: "William said how Mark always talked about Asia. It means a huge amount that they are here today putting the spotlight on what we are doing."

The Duke and Duchess heard from the Karbi people about how the charity helped relocate them to a village two hours from their homes in order to move them out the way of the elephants' migrant route.

They were both keen to speak to two mothers who were breastfeeding young children in slings.

William said: "They look very comfortable. That's amazing."

Before leaving, the couple were invited to put the finishing touches to the trunk of a much bigger elephant made of fibreglass which will be part of a fundraising campaign, Elephant Parade India, in which 300 painted elephants will be placed around India, from Delhi to Kerala.

William was the first to pick up a paintbrush and drew a blue circle around a red diamond shape. Kate was more adventurous and painted a flower.

Delhi-based painter Bulbul Sharma, 62, who is working on the project, said: "She took inspiration from my flowers and did a lovely flower. She seemed to thoroughly enjoy painting the elephant."