Caltex's shares jumped to a nearly two-year high of A$35.65, following the statement, which came in response to a report by Bloomberg on Tuesday that EG Group was considering a bid for Caltex.
Caltex said since announcing Couche-Tard's takeover proposal in November, "it has had approaches from a number of parties, including EG Group, who have indicated that they are potentially interested in making a proposal to acquire Caltex or some of its assets."
It added there was no certainty any binding proposal would be made by any of the parties.
Privately owned EG Group entered Australia in 2018 with the acquisition of supermarket giant Woolworths Group's petrol stations for A$1.7 billion, after Australia's competition watchdog blocked the sale of that business to British oil giant BP Plc.
EG Group in Sydney was not immediately available to comment on the Caltex approach. The phone was unanswered at EG Group's UK headquarters outside of office hours.
Caltex in November rejected an A$8.6 billion offer from Couche-Tard at A$34.50 a share, but said it would give the Canadian convenience store firm access to some private information to help it come back with a higher bid.
The two sides have yet to sort out the terms for that access.
Couche-Tard declined to comment on Caltex's statement on Wednesday.
Analysts said EG Group might run into issues with the Australian Competition and Consumer Commission, given that the UK group is among the top four petrol retailers in the country and would be bidding for a network that accounts for around 16% of petrol retail sales.
However they said the concerns would be different than with BP's bid for Woolworths' petrol stations, which would have eliminated discount competition in the market.
"It could be argued that an EG/CTX Convenience combination might create a stronger third/fourth ranked competitor in the retail market," Credit Suisse said in a note on Wednesday.
The heightened interest in Caltex comes after the surprise re-entry of Caltex's former co-owner Chevron Corp into Australian petrol retailing, buying Puma Energy's business for A$425 million.
As a result of that deal, Caltex has been forced to give up its brand and will have to spend A$165 million to rebrand its petrol stations, reviving the old Ampol name.
($1 = 1.4550 Australian dollars)
(Reporting by Sonali Paul; editing by Richard Pullin)