London Couples who have more than two children are being irresponsible by creating an unbearable burden on the environment, the Government’s green adviser has said.

Jonathon Porritt, who chairs the Government’s Sustainable Development Commission and was Tony Blair’s adviser on the environment, said that curbing population growth through contraception and abortion must be at the heart of policies to fight global warming.

Political leaders and green campaigners should stop dodging the issue, he said. A report by the commission, to be published next month, will say that governments must reduce population growth through better family planning.

“I am unapologetic about asking people to connect up their own responsibility for their total environmental footprint and how they decide to procreate and how many children they think are appropriate,” Mr Porritt said.

“I think we will work our way towards a position that says that having more than two children is irresponsible. It is the ghost at the table.”

Mr Porritt has two children.

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