The ministerial team at the newly-created Department for Energy and Climate Change (ECC) has been confirmed, although the new department's precise remit is still being finalised.

Mike O'Brien MP, a minister at the Department of Work and Pensions since 2007, and Lord Hunt, parliamentary under secretary at the Ministry of Justice, have been appointed as ministers working beneath the newly-installed secretary for energy and climate change Ed Miliband.

It has also been confirmed, Joan Ruddock, parliamentary under secretary at Defra with responsibility for climate change, will continue as parliamentary under secretary at the new department.

However, a spokeswoman for the new department said that the precise portfolios for the new ministerial team had not yet been finalised and it had not yet been decided if responsibility for energy and climate change would be split between O'Brien and Lord Hunt.

She added that it was hoped that the new department would be moved into a dedicated building in Whitehall Place by the end of the week and that its exact remit would be finalised.

While it is relatively clear that the Department for Business Enterprise and Regulatory Reform's (BERR's) will be moved wholesale into the new department, it remains uncertain which components of Defra's work on climate change will be moved. Initiatives to curb waste levels and climate change adaptation measures such as flood defence improvements, for example, could easily sit in both departments.

The spokeswoman for ECC said that despite the creation of the new department, the government's climate change strategy would continue to stretch across multiple portfolios and consequently the ECC and Defra would work "very closely " together regardless of where responsibility for areas such as waste and climate adaptation end up.

The creation of the new department comes as development charity Oxfam today published a 100-page report criticising a previous lack of coherence in the climate change policies adopted by both the government and many leading businesses.

The report highlights some of the opposing climate change policies adopted by Defra and BERR, which have repeatedly taken contrasting positions in their approach to how the UK should meet the EU's targets on renewable energy and carbon emissions.

Barbara Stocking, head of Oxfam, welcomed the creation of the new department as an opportunity to bring an end to the conflicting policies. "Too often it has been a case of the left hand having no idea what the right hand is up to, and this [new department] must now bring a much-needed cohesiveness to government policies," she said. "With global climate and energy security at stake, the government must now demonstrate powerful leadership."

The report also criticised a number of businesses and business groups for taking contradictory positions in their approach to climate change. In particular, it accused E.ON and Shell of promoting their green credentials while pursuing respective plans to build a new coal-fired power station at Kingsnorth and expand carbon-intensive tar sands operations in North America.

The CBI was similarly accused of undermining its own support for the development of a low carbon economy by lobbying for the building of new coal-fired power stations and airport capacity.

"Taking decisions now that will increase carbon emissions makes no sense at such a critical time," said Stocking. "We must switch to low-carbon and greater energy efficiency if we are to begin to stem the devastating effects of climate change already being felt by millions of poor people around the world, despite them being the least responsible."

However, the CBI's director of environment policy, Neil Bentley, defended the organisation's position. "Business has committed to do what it takes to tackle climate change and Oxfam describes the targets set by our members as "laudable and ambitious"," he said. "We would have our head in the clouds, however, if we did not consider the practical issues of moving to a low carbon economy."