Bar and cafe owners say they will present the government with a multi-million euro damages claim if it presses ahead with plans to close all smoking rooms within two years.

The hospitality industry lobby group KHN says a transition period of a minimum of five years is necessary to earn back the investment in expensive ventilation systems and separate rooms.

A survey of members showed the average bill for a smoking room has been €12,500 and without a longer transition period, many bar owners will not be compensated for the cost, chairman Robèr Willemsen told the Telegraaf.

In February appeal court judges ruled cafes and bars should close their special smoking rooms, which they set up when the ban on smoking was introduced in 2008.

The case was brought by Clean Air Nederland which argued that by allowing special smoking rooms, the Netherlands was breaking the terms of an agreement with the World Health Organisation.

In that agreement, the Netherlands said it would take steps to stop people being exposed to tobacco smoke in ‘indoor public places’. The court has now ruled this also applies to smoking rooms in cafes and bars.

The KHN said in April that the ban on smoking rooms will lead to increased noise and other problems for locals because four in 10 cafe and bar owners have no designated outdoor area where smokers could stand.