CAMPAIGNERS have warned council efforts to reduce harmful pollution in the city could 'not be enough.'
By October this year Portsmouth City Council will have to prove to the government that it is able to improve air quality to the same effect as a clean air zone, as part of two ministerial directives.
If it is unable to do so a mandatory clean air zone, that could see drivers in the city charged a fee, will be put in place.
It comes after the Department for Environment, Food and Rural Affairs (Defra) raised concerns about pollution 'hotspots' in the city including Mile End Road and near the Hope Street roundabout.
In an effort to improve levels of pollution council bosses have asked government for help with requests including free bus passes, money for electric taxis and scrapping housing targets.
But air quality campaigners are fearful that more is needed. Green party activist Tim Sheerman-Chase said: 'I worry that so far the council has not shown Defra that is will achieve compliance in the time frame needed.
'It seems like a lot of work on this has been kept private.
'I probably would not mind if they imposed a clean air zone but they take about two years to be put in place.
'My concern still is that they might not be able to meet the levels required, I think they will struggle.'
Mike Dobson, from Friends of Old Portsmouth, agreed. He said: 'The government is belatedly holding Portsmouth City Council to account on this.
'It has all been done quite secretly as well. They did not make their targeted feasibility study available to the public last year.
'Many other clean air campaigners are seriously worried that the council is not going to achieve the legal limits required to reduce air pollution. The ministerial directives have come about as a result of this.'