WASHINGTON, May 14 (Reuters) - Verizon, AT&T ( T )

and T-Mobile said on Thursday that they agreed in

principle to form a new joint venture that seeks to address

long-time coverage gaps especially in rural areas by using

satellite-based technologies.

The largest U.S. wireless companies said the plan seeks to

end nearly all dead zones without mobile service. The plan also

aims to ensure redundant connectivity during natural disasters

and improved network performance.