WASHINGTON, March 3 (Reuters) - Lockheed Martin LMT.N plans to unveil a new "affordable" cruise missile on Monday with a cost of about $150,000 and a range of over 500 miles (800 km) as the defense contractor works to tap a U.S. need to deter Chinese ambitions in the Pacific.

Russia's invasion of Ukraine has pushed U.S. and other countries' thinking about armaments toward a new strategy known as "affordable mass," meaning having plenty of relatively cheap weapons at the ready.

The Common Multi-Mission Truck (CMMT) missile concept is a new product that aims to develop a family of low-cost modular weapons from Lockheed and its partners' existing catalog of components.

The CMMT missile is designed to fill a gap between lower-cost standoff glide weapons and more expensive cruise missiles, Scott Callaway, Director, Affordable Mass, Lockheed Martin Missiles and Fire Control told Reuters in a recent interview.

If the Pentagon decides to buy the new offering, Callaway said Lockheed could make 2,500 a year - once a production line was running.

CMMT is "a subsonic, low-cost, long-range cruise missile," Callaway said. Its low-cost turbine engines cannot, however, compete with cruise missiles such as Lockheed's AGM-158 Joint Air-to-Surface Standoff Missile.

The JASSM is a 1,000-pound missile costing over $1.5 million per item.

The industrial scale of the war in Ukraine has highlighted the necessity for deeper inventories of relatively inexpensive weapons.

CMMT is designed to be modular, allowing for diverse variants to meet various mission requirements.

These include a longer-range version - deployable from aircraft like the C-17, fighters and bombers - as well as a shorter-range version.

A maritime strike variant is also envisioned, potentially to be employed in swarms with varying seeker mechanisms for greater effectiveness.

Callaway said Lockheed Martin was aiming to sell the basic air vehicle for $150,000 per unit, which it considered competitive.

The United States is amassing an arsenal of abundant and easily-made anti-ship weapons as part of efforts to push back against Chinese assertiveness in the Indo-Pacific region.

(Reporting by Mike Stone in Washington; Editing by Kevin Liffey)

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