The couples, both from Dundee, have defied new rules introduced by the city council that ban smokers from adopting and fostering children unless they agree to keep their homes smoke-free.

Under the scheme, prospective foster parents are required to sign a pledge promising not to light up under their own roof.

Of 27 existing foster parents in the city who smoke, 25 have indicated that they will accept the new guidelines. The two remaining couples are refusing to comply, even though they face being stripped of their approved foster-parent status.

Critics say children will suffer because of the “draconian and discriminatory” rules.

An official report on the Family Placement smoking policy, which is backed by the city’s social work committee, states: “Two households have indicated they will not comply with the revised policy.

“In order to progress towards a situation of full compliance the Family Placement Service will continue to work with these two carers to try to reduce the effect of their smoking on the young people in their care and, when the placements end, to review their approval.”

A spokesman for the council said that the carers could be removed from the approved list if they continued to defy the guidelines.

Before the guidelines were introduced, 49 of 132 fostered youngsters in Dundee lived in households where someone smoked.

Officials said they introduced the changes after examining scientific evidence that passive smoking harms children and those who live in smoking households.

They claim that each year in the UK more than 17,000 children aged under five are admitted to hospital with passive smoking-related illness.

Claire Dickinson, of the Fostering Network, said: “It is clearly better for a child to live in a smoke-free environment, but being a good foster carer is about much more than whether or not you smoke.”

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