The veto was proposed by an interest group of farmers, sole proprietors and freelancers, who argued that the cost on businesses would be excessive, while the goal of an increased tax take would not be met.

Councillor Alojz Kovšca said on behalf of the proponents of the veto that an answer should be provided to the question whether the expected benefits outweigh the costs.

The interest group argues that novelties are being introduced while the effects of the introduction in 2013 of special software that prevents the deletion of receipts have yet to be evaluated.

Kovšca also said that the new system would not reduce the informal economy in cases when no receipts are issued at all or when services are provided by illegal subjects.

Until penalties for those who work illegally, without registration, are lower than penalties for whose who pursue an activity legally, "we cannot speak about the state being interested in regulating this area", he said.

The government meanwhile argues that the bill is designed to curb the informal economy by making it harder for businesses to cheat on retail revenue.

The online system will send all receipts automatically to the Financial Administration (FURS) for verification prior to them being printed by businesses.

The government plans to raise an additional EUR 50-100m in VAT receipts a year, while the setting up of the system is expected to cost FURS around EUR 2m. Cost for businesses per cash register have been estimated at up to EUR 300.

The National Assembly now needs to support the bill with an absolute majority of 46 votes to override the veto. MPs already voted 48 to 30 in favour the first time around.

The re-vote will be taken at an extraordinary session on Monday.