U.S. regulators proposed easing restrictions on satellite companies in a move aimed at freeing more airwaves to feed the growing demand for wireless broadband services.

The Federal Communications Commission voted unanimously on Thursday to seek comment on a plan to let satellite companies partner with other business seeking to build land-based networks or to lease their spectrum to other companies in a secondary market.

The FCC also sought public comment on allowing satellite companies to relinquish spectrum in return for proceeds from future airwaves auctions.

The plan could affect about 90 megahertz of spectrum, held by companies such as SkyTerra Communications Inc, TerreStar Corp and Globalstar Inc, that is particularly suited to broadband delivery.

The FCC's National Broadband Plan aims to open up 500 megahertz (MHz) of airwaves by 2020.

The FCC is also trying to persuade broadcasters to relinquish about 125 megahertz of spectrum under a voluntary plan.

The satellite move comes after the FCC in late March approved an application by Harbinger Capital Partners to acquire SkyTerra, a mobile satellite services company.

Harbinger's approval allows SkyTerra to build a land-based nationwide broadband network, which is in line with the FCC's goal to provide broadband access to all Americans including households located in rural areas of the United States.

But Harbinger needs FCC approval before leasing wholesale spectrum capacity to the top two wireless providers: AT&T Inc and Verizon Wireless, which is a venture between Verizon Communications Inc and Vodafone Group Plc.

Efforts to free up spectrum by the FCC, which wants more broadband competition, could help Deutsche Telekom AG's U.S. unit, T-Mobile, which is seeking more airwaves to better compete with AT&T and Verizon Wireless.

President Barack Obama has backed Genachowski's plans to boost spectrum to support the wireless industry, as more and more consumers drop their landline connections for smartphones and other wireless devices.

The White House has said some estimates suggest that the next five years will see an increase in wireless data of between 20 times and 45 times 2009 levels.

(Reporting by John Poirier; Editing by Tim Dobbyn)