The days of big shopper docket fuel savings are over after Coles and Woolworths agreed to limit discounts to four cents a litre.

The Australian Competition and Consumer Commission on Friday announced the two supermarket giants had agreed to the four cent a litre maximum discount limit.

Coles and Woolworths have also agreed to stop funding the discounts through their supermarket division and any future discounting will need to be covered by their fuel retailing business.

The two supermarket chains made the voluntary undertakings to address the competition watchdog’s concerns their discount offers would reduce competition in the fuel retail sector.

The move was sparked by an ACCC investigation into the effects of the shopper dockets, which was sparked by extended periods of eight cents a litre discounts from both companies.

“We were concerned that those offers could have longer-term effects on the structure of the retail fuel markets and also short term effects of increasing general pump prices in those markets,” ACCC chairman Rod Sims said.

The ACCC said some fuel retailers had complained they could not afford to match the eight cents per litre discounts because they were subsided by Coles and Woolworths’ supermarket divisions.

The four cent a litre limit for offers to supermarket customers will apply from January 1.

Coles managing director Ian McLeod said the supermarket chain did not believe its discounts amounted to a breach of law but recognised the ACCC’s concerns.

“Coles has agreed to address the concern that larger discounts could adversely affect competition over time and from 1 January 2014 Coles will no longer offer any fuel discounts above the four cents per litre to supermarket customers,” he said.

But he said Coles would continue to offer its four cent per litre fuel discounts to its customers.