Tony Blair has pledged to "push green issues back up the political agenda" aiming to reaffirm the government's commitment to the environment. Blair's comments came in what was the first major environmental speech of his premiership. However, he was criticised by both his political opponents and some members of the environmental lobby over his eco-commitments to date.

In his keynote speech at the CBI and Green Alliance conference on the environment, the prime minister called for "a constructive partnership - government, business, the green movement and the public". He said the partnership must "seek global solutions to global problems".

Speaking this morning Blair paid tribute to the members of the cabinet responsible for the environment saying: "Through John Prescott's leadership, and the hard work of Michael [Meacher] we can point to measurable achievements. We are on track to meet our Kyoto targets. Air quality is improving. London now has the cleanest river of any major city."

However, an interview claims that Michael Meacher, the environment minister, is in fact being held back by Blair in the development of environmental policy.

Tory spokesman Damian Green claims in the exclusive epxNews interview that whilst Meacher is held in high regard by the green lobby, his efforts are being frustrated by the PM. Says Green: "I think Michael's problem is that whatever he wants to do personally, and he is an honourable, straight-forward, honest and decent man, is that the green case doesn't have any clout inside this government and that's what the green groups themselves tell me, that they have perfectly good relations with Michael Meacher and respect for him but they know that when he goes up to Blair there's just nothing there."

The prime minister used the speech to say that the government was making the right advances on the environment. On the GM food debate Blair said the government had not been pressed into a positive stance by "wicked multinationals and politicians", adding he was fully aware of the potential impact on biodiversity and people's concerns about health. "I am neither pro nor anti. I simply say: let us evaluate the technology, test it and then make a judgement; rather than ban it before we even look at it," he said.

Blair concluded by saying: "We have one common aim: to show how by doing good to the environment, we enrich our lives, in quality and prosperity. Concern for the environment is not a yoke on our necks. It is the lifting of the yoke. The burden is lighter. The way is clearer; I believe it can be done."

Speaking after the event one environmental campaigner who listened to the speech told epxNews: "The speech was well delivered but lacked substance. The prime minister was waffling when it came to answering direct questions - the detail is still missing."