Barack Obama has named a Nobel Prize-winning physicist as his nominee for energy secretary and a new "climate tsar" to oversee the battle against global warming.

The US president-elect said on Monday that his choice of Steven Chu as energy secretary and Carol Browner to lead a White House council on energy and climate, signalled his determination to tackle global warming quickly and develop alternative forms of energy.

Obama had vowed to make climate change and the environment a top priority during his election campaign and on Monday he pledged to "move beyond our oil addiction and create a new hybrid economy".

Chu is director of the Lawrence Berkeley National Laboratory in Berkeley, California, and is a leading advocate of reducing greenhouse gases by developing new energy sources.

'Valuing science'

"His appointment should send a signal to all that my administration will value science. We will make decisions based on the facts, and we understand that facts demand bold action," Obama said.

Browner is an ally of Al Gore, the former vice-president turned Nobel Prize-winning environmental campaigner, and headed the Environmental Protection Agency (EPA) in Bill Clinton's administration.

Carol Browner is a former Environmental Protection Agency head [AFP]

"We can spark the dynamism of our economy through a long-term investment in renewable energy that will give life to new businesses and industries with good jobs that pay well and can't be outsourced," he said.

"We must also recognise that the solution to global climate change must be global," he added.

Obama also met members of his new national security team on Monday, in one of several meetings he is expected to hold with his national security team between now and when he takes office on January 20.

His transition team said the focus of the meeting was on challenges around the world, so they are prepared when the new administration takes office.