Recent research by Sainsbury's found that the lifetime cost of owning a dog stands at around £9,000, while taking care of a cat can lead to costs of over £7,000.
Mr Johnson suggested that the rising cost of looking after animals may be linked to an increase in the number of pets being abandoned.
He added: "It's important that owners and potential purchasers fully appreciate the financial commitment related to owning a cat or dog - this is rising at above the rate of inflation.
"Pet insurance need not be expensive and there are some very competitive premiums out there, like our own, which provides excellent cover and peace of mind."
Earlier this year, research by Sainsbury's Finance found that 1.8 million pet insurance claims for veterinary treatment for dogs and cats are made every year.
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