The European Commission will step up attempts to tackle climate change this week amid concern that international progress is again being stalled by the US.

Uninterrupted by France's No vote, the European Union's executive will also consider prospects for reducing greenhouse gas emissions from aviation as part of “Green Week”, which this year will concentrate on climate change.

Stavros Dimas, the European Union's environment commissioner, said: “Climate change is one of our biggest environmental challenges and a major threat to our economies. Our aim in bringing together key players and stakeholders during Green Week is not only to listen but also to try to move towards workable and cost-effective solutions, particularly in view of the further efforts that will be needed to achieve global reductions in emissions of greenhouse gases.”

But Green Week, timed to lead up to the United Nations World Environment Day this Sunday, when mayors from around the world will adopt measures to create greener cities, will take place against a backdrop of uncertainty over the prospects for international action on climate change.

Tony Blair, the UK prime minister, is visiting leaders of EU member states and the Group of Eight industrialised nations over the next few weeks in preparation for the UK's presidency of the EU from July and the G8 summit in Gleneagles on July 6. He will discuss climate change, which he has made one of his twin priorities for the G8 this year, along with Africa. But the leak of a memo purporting to be the draft text of a G8 statement on climate change, to be issued at Gleneagles, dismayed some environmental campaigners. The document lacked any reference to specific targets for the reduction of greenhouse gas emissions. However, the US has long and consistently refused to be tied to targets for emissions reduction such as those imposed by the UN-brokered Kyoto protocol on climate change.

Another sensitive area surrounds plans to deal with climate change beyond 2012, when the main provisions of the Kyoto protocol expire. Business leaders in the UK called last week for the government to provide “greater certainty” to businesses by extending emissions reduction targets to 2025.

But the US is adamantly opposed to discussions of actions beyond 2012. Senior US officials have said such discussions would be “premature” and repeated this view at a meeting of Kyoto countries in Bonn earlier this month. The G8 meeting is more likely to see agreement on the importance of investing in research and development into technologies that will help reduce emissions, such as renewable energy sources and the capture and storage of carbon. The US spends more than $5bn $5bn (€4bn, £2.8bn) a year on technologies and research related to climate change.