Michael Meacher is not a lone green voice in government, Downing Street has said.

Number 10 issued a strong rebuttal of an interview given by the environment minister in which he complained about the low priority given to green issues.

According to press reports, the environment minister had also fought to get on the ministerial delegation that will be going to the sustainable development summit in Johannesburg.

"The government made the environment a top priority last year in addition to health, education, crime and transport," said a Number 10 official.

"Tony Blair has taken a lead in a government which is committed to dealing with environmental issues."

Other ministers, led by deputy PM John Prescott - who has "a record second to none" on green issues - were also heading key initiatives, Downing Street argued.

Clare Short was leading on development issues and Margaret Beckett headed a department set up "to ensure that sustainable development is at the heart of policy".

"The government as a whole is committed and there are other ministers who are heavily involved in these issues."

Meacher had claimed he is a "lone voice" in government when it comes to promoting green issues.

Hitting out at a range of cabinet colleagues, and appearing to question Tony Blair's commitment to eco-friendly policies, the environment minister also said the government was not prepared to take the tough decisions needed to prove its green credentials.

Downing Street had already been forced to backtrack on an attempt to drop Meacher from the UK's delegation to the Johannesburg Earth summit, taking place later this month.

The minister appeared to be hitting back, explicitly including the Treasury, the Department for Trade and Industry and the Department for Transport in a list of ministries failing to put the environment at the heart of their policies.

In an interview with the Sunday Times, Meacher said he was determined to keep pushing green issues to the top of the government's agenda.

"I make no bones about it. I don't think the government as a whole is yet ready to take the magnitude of the decisions I think are necessary," he told the newspaper.

Asked whether Tony Blair understood the threat to the environment, Meacher said: "I hope so. One is like a lone voice in the wilderness."

He then launched a series of attacks on green policy failures ranging from transport to regional policy.

Questioned on the government's plan to build 200,000 new homes in the South East, Meacher said more houses were needed but "I would like to see a regional policy that spreads industry more across Britain".

He said the failures extended to the centre of the government. "It goes a great deal wider than me, right to the centre, the Treasury, DTI, they are all involved."

And on transport he questioned the government's position on increasing capacity to meet rising demand. "The skies are larger than roads, but capacity is not indefinite," he warned.

The minister added that building a new airport at Cliffe in Kent, one possibility mooted by the transport secretary, would have "huge environmental consequences".

And he said the government was failing to persuade drivers to use their cars less.

"We tried but I have to say I don't think we've succeeded. You could say we haven't tried hard enough," Meacher said.