OTTAWA - Prime Minister Stephen Harper will attend the Copenhagen conference on climate change next month.

Spokesman Dimitri Soudas said a “critical mass” of world leaders is now attending the conference, though there will not be an official leaders’ meeting. China’s premier announced today that he is attending, and U.S. President Barack Obama will also be there briefly.

The news came as Liberal leader Michael Ignatieff said his party, if elected, would make “the most significant investment in clean energy… this country has ever seen.”

In a speech meant to stake out his party’s position on the environment in advance of the international summit on climate, Ignatieff told an audience at Laval University the Liberals would quadruple Canada’s use of renewable energy by 2017, the country’s 150th birthday.

“We’ll promote green construction and put in place new transit systems to reduce pollution – like high-speed rail. We’ll use new energy-saving technologies like 'smart meters' for our homes and businesses, and ‘smart' electrical grids to reduce wasted energy,” he said.

Ignatieff said the Liberals would:

* adopt the toughest vehicle emissions standards in North America;

* adopt a new clean energy act;

* adopt a national fresh-water strategy;

* create maritime protected areas;

* adopt a special environmental plan for the North;

* set mandatory clean energy procurement standards and

* make climate change “the centre of our international development policy.”