The mystery vehicle that cost taxpayers more than $3,700 to ferry Health Minister Jane Philpott around on ministerial business on two occasions earlier this year was a luxury Lexus, CBC News has learned.

Philpott's office has repeatedly refused to tell reporters what kind of vehicle a Toronto limousine service used in shuttling the minister around, saying only that it wasn't a limousine.

However, Reza Shirani, owner of the company that Philpott hired to get to events and for trips between the airport and her Stouffville, Ont., home, says the vehicle was a Lexus ES 300.​

The Lexus ES 300 is a luxury sedan with a suggested retail price that starts at $44,700. On its website, Lexus touts the ES 300 (Elegant Sedan) as a vehicle designed "to excite the senses of the most discerning individuals" and invites buyers to "create your own version of luxury."

While it can often be found in the fleets of limousine services, the Lexus ES 300 does not generally fall into the category of limousine.

The limousine service Health Minister Jane Philpott had hired to ferry her around the Greater Toronto Area earlier this year used a Lexus ES 300. (Lexus )

Few standard car rental companies appear to keep Lexus ES 300s in their inventories. To rent one, you generally have to turn to specialized luxury car rental agencies. Rates quoted to CBC News to rent a Lexus ES 300, without a driver, in the Toronto area ran from $80 to $170 a day, plus tax. One service, which provides a Lexus ES 300 and driver, quoted the cost at $50 an hour.

Is it a limo?

Whether the vehicle Shirani's company provided is considered a limousine could affect whether Philpott faces allegations of misleading Parliament. In a document signed by Philpott and tabled in the House of Commons in June in response to a question from Conservative MP Dan Albas, Health Canada said she had not charged taxpayers for limousine rental between November 2015 and April 2016.

The interior of the 2016 Lexus ES 300. The manufacturer vaunts its luxury features. (Lexus) Philpott has come under opposition fire over the past week for the cost of some of her travel, including a controversial trip she took with Shirani's company on March 31. Philpott racked up a tab of $1,700 in one day to attend four events in the Greater Toronto Area, with stops in Hamilton, Toronto and Markham.

The opposition has also been quick to point out that Shirani campaigned for Philpott in last year's general election.

On Thursday, Philpott apologized for what she described as "excessive costs" for travel. The minister said she will ensure it doesn't occur again and pledged to personally reimburse taxpayers $3,703 for travel on March 31 and July 12.

Invoices, obtained by the Conservative Party under the Access-to-Information Act and shared with CBC News, show Philpott has used Shirani's company many times, including for travel between her home and the airport. Each of the invoices is marked as "sedan airport transportation."

Car service bills itself as 'luxurious'

In invoices issued between Feb. 5 and March 30, Shirani's company is listed as "Executive Limousine Livery Service Inc." – the same company name he lists on his LinkedIn profile. Later invoices, in May and June, list the company name as Executive Sedan Service Inc.

Shirani bills his company as "the industry's leader in providing luxurious limousine transportation to corporate and VIP clients," including "specialized services to pharmaceutical companies and law firms."

Invoices in February and March for trips between the airport and home were charged to a personal credit card and the invoices are addressed to Philpott's home in Stouffville, Ont.

A receipt in March for $526.29 was sent to Cindy Dawson, Philpott's scheduling assistant in Ottawa. Three other invoices, dated in March, May and June, were sent to Philpott's office in Ottawa and indicated the trips had been charged to a department credit card.

Among Health Minister Jane Philpott's events on March 31, 2016 was a tour of the Michael G. DeGroote Institute for infectious disease. (McMaster University)

None of the invoices provided to CBC News, however, relate to the controversial trip she took with Shirani's company on March 31 or a later trip she disclosed that took place July 12.

Shirani feels the whole thing is being exaggerated.

"They are all screaming about $1,700, but they don't know the circumstances. They don't know what my company did and what occurred, how long of a drive it was, how many hours of service it was. They're just talking about $1,700. It wasn't $1,700. It was $1,500 and some change, plus HST, that came out to that."

However, the promise to write a cheque and the revelation that the vehicle was a luxury Lexus hasn't silenced the Conservatives, who have dubbed Prime Minister Justin Trudeau's government "Limousine Liberals" in fundraising pitches to party supporters.

Is that a responsible use of taxpayers' dollars? I think not. - Colin Carrie, Conservative MP

Conservative MP Colin Carrie, who has asked ethics commissioner Mary Dawson to investigate Philpott's travel bills, said questions remain unresolved.

"She used taxpayers' resources to reward a partisan supporter at a rate that appears to be, from my research, about three times the going rate. … She paid more for one day than you could rent that car for a month.

"Is that a responsible use of taxpayers dollars? I think not."

Nor does the revelation that the vehicle was a Lexus rather than a limousine let Philpott off the hook when it comes to the question of whether she misled the House, Carrie said.

"At best, she's splitting hairs … It's a very nice car and the amount is outrageous."