OTTAWA - The federal government hopes to launch a second auction of wireless spectrum in 2012, and this time it may be open to foreign buyers, according to Industry Minister Tony Clement.

Clement said in a speech Monday he will soon launch consultations on the 700-megahertz spectrum with a view to holding an auction by the end of 2012.

As well, he says another round of consultations on the 2,500-MHz spectrum will begin early in the new year.

And Clement said the new spectrum auctions will likely be subject to new foreign ownership rules that are expected to expand ownership limits above the current 20 per cent.

Clement said he has also asked his officials to review whether tower sharing and roaming regulations are appropriate to encourage new entrants to the sector.

Even before the new rules are announced, opposition is building. The Communications, Energy and Paperworkers Union is lobbying MPs in Ottawa this week against lifting restrictions, saying it will cost jobs.

The 700-MHz spectrum is becoming available Aug. 31, 2011, because of the switch to digital TV. The spectrum is attractive to mobile phone carriers because of its range and better penetration of buildings.

The last auction of spectrum in 2007 raised about $4 billion for the federal government, increasing competition in the industry with the entry of new players such as Wind Mobile.