The birth of the baby boy in the early hours of Monday UK time sparked excitement across the world, including at the Wongarbon farm that hosted his parents seven months ago during their Australian tour.

Emily Carroll, mother of little Ruby, said it was exciting and sent her congratulations to the duke and duchess, who she and other members of the Woodley family had met at the property.

The visit occurred two days after the palace announced Meghan's pregnancy.

"Our family still feels grateful to have had that experience of being able to meet them and talk to them about the drought, as well as them becoming a family of three," Mrs Carroll said.

The so far unnamed boy, the seventh in line to the throne, weighed 3.26kg.

Meghan and the baby were both healthy and well, Buckingham Palace said in a statement.

Prince Harry beamed as he faced reporters alone in Windsor, west of London, where the couple live.

Mrs Carroll welcomed a break in a practice of the past 40 years.

"I'm happy to see Meghan didn't feel the responsibility to walk out of the hospital so soon after the birth like Kate did," she said.

"It was a more normal introduction to having a new baby in the family...

"It's great they got to keep their privacy until the dad [appeared to media], then Harry's informal and excited announcement was very sweet."

Dubbo mayor Ben Shields said the announcement of the expected baby on the eve of the couple's visit to the city was historic and made the international media's attention focus on the couple while they were in Dubbo.

"So Dubbo is obviously going to have a huge affection for these two for many years ahead," he said.

"...When they were here, they really did show they had a common touch, they were really in touch with people.

"...they really did have the concerns of ordinary folk in mind when they were meeting and greeting people.

"Whether it be little Luke Vincent, right through to farmers out on properties, they did have a concern, they wanted to know exactly what the drought was about.

"What Dubbo was about, the struggles in western NSW, what it's about, and that was really evident to me being up close and personal with them over that time."

The city would send its best wishes via mail to the couple at the birth of their first child, he said.

Speculation about the infant's name is growing, but Cr Shields had no guesses to offer.

"I wouldn't have the faintest idea what they're going to call their baby, but I've got no doubt there will be some sort of traditional link to it," he said.