Tucson-based Raytheon Missile Systems will add a combat-sensors division and responsibility for Raytheon’s United Kingdom business, under a consolidation plan announced today by its parent company.

Massachusetts-based parent Raytheon Co. said it is merging its six business units into four, to increase productivity and better meet customer’s needs.

The company said 200 jobs will be cut by the restructuring plan, which will go into effect April 1, but details of specific cuts weren’t disclosed. The plan is expected to save the company $85 million annually.

Raytheon has roughly 68,000 employees worldwide, while Raytheon Missile Systems employs about 10,500 people in Southern Arizona.

Under the plan, the new Raytheon Co. structure will consist of four businesses.

• A new unit, Raytheon Intelligence, Information and Services, will result from the combination of Raytheon’s Garland, Texas-based Intelligence and Information Systems business and its Dulles, Va.-based Technical Services unit. The businesses had combined sales of about $5.5 billion in 2012.

• The existing Missile Systems, Integrated Defense Systems and Space and Airborne Systems businesses, each will be expanded by the absorption of Raytheon’s McKinney, Texas-based Network Centric Systems business.

Missile Systems, one of Raytheon’s six business units and Southern Arizona’s largest private employer, will add the Combat & Sensor Systems division of Network Centric Systems, as well as responsibility for Raytheon UK.

Missile Systems President Taylor Lawrence will lead the combined business, which had sales of about $6.5 billion last year, the company said.

Raytheon Co. spokesman Jon Kasle said no further information was available regarding the impact on jobs or operations at Missile Systems. For now, operations will continue as they stand under the new reporting structure that becomes effective April 1, Kasle said.

Raytheon’s Combat & Sensing Systems division employs more than 1,900 people in operations in Indiana, California, Virginia and multiple locations in North Texas, according to a company overview.

The division develops and makes target acquisition, weapons fire control, reconnaissance and surveillance thermal imaging systems, such as night-vision equipment, as well as electro-optical and infrared combat sight and thermal imaging systems, advanced radio communications systems and networked sensing and battlefield-information systems.

Raytheon UK, based in Glenrothes, Scotland, specializes in defense and security electronics and is a prime contractor to the UK Ministry of Defence. The company, which recently opened a foundry to make silicon carbide for advanced electronics, employs more than 500 people in research, development and manufacturing across the U.K.