SkyTerra Communications, Mobile Satellite Ventures Set First-Quarter Conference Call for 10 a.m. Tuesday, May 15, 2007.

RESTON, Va. -- SkyTerra Communications, Inc. (OTCBB:SKYT) and its subsidiary Mobile Satellite Ventures LP announced today that a conference call to discuss 2007 first-quarter financial results and other developments is scheduled for 10 a.m. Tuesday, May 15. The call will be led by Alexander H. Good, Chief Executive Officer and President of SkyTerra and Vice Chairman, CEO and President of MSV, and Scott Macleod, Executive Vice President and Chief Financial Officer of SkyTerra and MSV.

Dial-in Instructions:
The toll-free dial-in for the teleconference is 866-770-7051.
International callers should dial 617-213-8064. The access code
is 41555657. Please allow at least 10 minutes prior to the
scheduled start time to connect to the teleconference.

Dial-in Audio Replay:
A replay of the teleconference will be available beginning at Noon
EDT May 15, 2007 until 11:59 p.m. ET on May 29, 2007. To access
the replay, please call 888-286-8010, access code 32388372;
international callers should dial 617-801-6888.

About SkyTerra Communications, Inc. and Mobile Satellite Ventures

MSV is developing a hybrid satellite-terrestrial communications network, which it expects will provide seamless, transparent and ubiquitous wireless coverage of the United States and Canada to conventional handsets. MSV holds the first FCC license to provide hybrid satellite-terrestrial services. MSV plans to launch two satellites for coverage of the United States and Canada, which are expected to be among the largest and most powerful commercial satellites ever built. When completed, the network is expected to support communications in a variety of areas including public safety, homeland security, aviation, transportation and entertainment, by providing a platform for interoperable, user-friendly and feature-rich voice and high-speed data services. MSV is majority owned and controlled by SkyTerra Communications, Inc. (OTCBB:SKYT). For more information please see: http://www.msvlp.com.

Statement under the Private Securities Litigation Reform Act 

This news release may contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act, with respect to plans described in this news release. Such statements generally include words such as could, can, anticipate, believe, expect, seek, pursue, proposed, potential and similar words. Such forward-looking statements are subject to uncertainties relating to the ability of SkyTerra and MSV to raise additional capital or consummate a strategic transaction or deploy the next generation system, as well as the ability of SkyTerra and MSV to execute their business plan. We assume no obligation to update or supplement such forward-looking statements.