Caltex has made a confidential offer for the Woolworths fuel business

A petrol bowser fashioned into a balloon inflator at Customs House in Sydney. Cameron Spencer/Getty Images for Nissan

Caltex Australia says it has made a conditional and confidential offer to Woolworths for its fuel business.

The company also says it wants to continue its “successful” fuel alliance with the supermarket chain.

Caltex is the exclusive supplier of petrol and diesel to Woolworths with annual sales volumes of 3.5 billion litres a year, a deal linked to Woolworths’ continued ownership of the business.

The Woolworths petrol business turned over $4.61 billion in the 2016 financial year, a fall of 18.1% on the previous 12 months. Sales were impacted by changes to the alliance with Caltex and declining average fuel prices.

“The sale process is ongoing, and any transaction remains uncertain and is expected to take time to complete,” Caltex said in a statement to the ASX.

Last month the troubled retailer Woolworths confirmed it was looking at a sale, reported to be for as much as $1.5 billion, of its petrol business.

The retailer says it has received incomplete and conditional proposals from a number of parties.

In August, Woolworths posted a full year net loss of $1.23 billion, as the retailer exits the hardware industry, restructures and rebuilds its supermarket business.

Total revenue for 2016 slipped 0.8% down to $60.65 billion.

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