You spend weeks planning the perfect proposal, only to be upstaged by a baby hippopotamus when you finally pop the question.

Adorable hippo Fiona stole the limelight during a couple's engagement photo at Cincinnati Zoo in Ohio, reports The Telegraph.

Nick Kelble and his girlfriend Hayley Roll regularly visit Fiona and were delighted their favourite animal witnessed the proposal.

The ecstatic new bride-to-be wrote in a message to her boyfriend on Instagram: "We're so happy Fiona could be there on our special day. Here's to many more years of going to zoos with you."

Advertisement

She added in an interview with the Daily Buzz: "We went to the zoo for our one-year anniversary and Fiona was in the window.

"Nick, my boyfriend, and I were waiting in line to get our photo taken with Fiona and I gave my cell phone to someone to take the photo and when I turned back around, Nick was on one knee proposing."

Fiona became the first Nile hippo born at the zoo in 75 years back in January and had a fight to survive after her mother gave birth six weeks early.

This cutie is 9-months-old today!!! With the cooler weather upon us keep in mind that temperatures must be 50 degrees...

Posted by Cincinnati Zoo & Botanical Garden on Tuesday, 24 October 2017

"Full term hippos usually weigh between 50-110lbs," the zoo says. "Fiona only weighed 29lbs when she was born 6 weeks premature. She is the smallest hippo to ever survive."
The zoo say Fiona is a "little hippo with a big personality".

"As Fiona continues to grow, the many facets of her complex personality are really starting to show!" they said earlier this year.

"It's fascinating to watch how the different elements of her personality seem to reflect the natural history of the hippopotamus."