Five legal challenges to the Government’s plans for a new runway at Heathrow will reach the High Court this week.

One case involves a coalition of local authorities, London mayor Sadiq Khan and campaign group Greenpeace, who argue the Government’s Airports National Policy Statement (NPS) backing Heathrow expansion should be quashed.

The councils will say that the third runway can only be built by demolishing thousands of homes and making life noisier and unhealthier for millions of people, while large increases in road traffic will worsen pollution.

Shirley Rodrigues, London’s deputy mayor for environment and energy, said: ‘Toxic air pollution leads to thousands of premature deaths in the capital every year and stunts the development of children’s lungs.

‘Heathrow expansion would worsen air quality further, with dire consequences on the health and quality of Londoners’ lives. There is no commitment to new rail infrastructure and expansion is expected to result in at least 40,000 additional vehicles on the roads every day. Together with serious concerns about increased disruption from noise, we had no choice but to challenge this decision.’

The coalition, which includes Hillingdon, Wandsworth, Hammersmith and Fulham, Richmond upon Thames and Windsor and Maidenhead councils, argues that transport secretary Chris Grayling ignored crucial facts when adopting the NPS. This included information about surface access provided by the mayor.

Mr Grayling is also accused of failing to produce an environmental report showing which communities were going to be affected by noise, publishing instead indicative flightpaths which are ‘almost meaningless’, according to the case against.

The local authorities will argue that if Mr Grayling is found to have acted unlawfully, the NPS should be quashed, which would mean that the selection of the northwest runway option in preference to the other proposals – Gatwick and Heathrow Hub –would have to be reopened.

Friends of the Earth, represented by law firm Leigh Day, said it is ‘leading on the climate change arguments’. Its case is due to be heard on Wednesday (13 March).

The group argues that the Government’s decision to allow expansion is unlawful, ‘fundamentally because it failed to have regard to the desirability of mitigating climate change in the context of the UN’s Paris Agreement and the non-CO2 contribution of aviation to global warming’.

Rowan Smith, solicitor at Leigh Day, said: ‘The absurdity of the Government giving the green light to airport expansion, when all the signs it ignored pointed to the need to make even deeper CO2 cuts in order to avoid catastrophic climate change, is clear.

‘As a result of this legal challenge brought by our clients, the Government has already been forced to concede that it had material in its possession, which indicated more stringent emissions targets were likely to be necessary, before allowing the Heathrow expansion to go ahead. ‘

A Department for Transport spokesperson said: ‘Expansion at Heathrow is a critical programme which will boost the economy, increase our international connections and create tens of thousands of new jobs.

‘As with any major infrastructure project, the Government has been anticipating legal challenges and will robustly defend our position. We recognise the local impact of any expansion, which is why a world class package of mitigations would need to be delivered.’