(Reuters) - U.S. and Saudi Arabian companies signed tens of billions of dollars of business deals on Saturday as Riyadh sought help to develop its economy beyond oil during a visit by President Donald Trump.

National oil firm Saudi Aramco said it signed $50 billion of agreements with U.S. firms. Energy Minister Khalid al-Falih said deals involving all companies totaled over $200 billion.

Some deals had been announced previously, while others were memorandums of understanding that would require further negotiations to materialize. Below are major announcements:

-- GE said it signed $15 billion of business deals with Saudi Arabia, involving almost $7 billion of goods and services from GE itself. They ranged from the power and healthcare sectors to the oil and gas industry and mining. Among projects, GE will help make power generation more efficient, provide digital technology to the operations of oil firm Saudi Aramco, and cooperate in medical research and training.

-- Exxon Mobil and Saudi Basic Industries agreed to conduct a study on a potential petrochemical project in San Patricio County, Texas. A final decision is expected sometime in 2018. The project would include an ethane cracker with a production capacity of 1.8 million tonnes of ethylene per year to feed a monoethylene glycol unit.

-- Raytheon will establish a Raytheon Arabia business unit and help to develop Saudi defense, aerospace and security capabilities.

-- Lockheed Martin will support the final assembly and completion of an estimated 150 S-70 Black Hawk utility helicopters in Saudi Arabia.

-- General Dynamics will help to localize design, manufacturing and support of armored combat vehicles.

-- Begin the design and selection process for offshore drilling rigs as part of a $7 billion investment over 10 years with Rowan Companies to own and operate such rigs.

-- Additional well services and studies into rig movements as an extension of a joint venture with Nabors. The venture is to see $9 billion of investment over 10 years period and create 4,000-5,000 new Saudi jobs.

-- New joint venture between Saudi Aramco and National Oilwell Varco to make high-specification drilling rigs and equipment in the kingdom; it is to involve $6 billion of investment over 10 years.

-- Jacobs Engineering: MoU worth $250 million to localize design, engineering, procurement, construction and project management services for the oil and gas industry. It is expected to create 300 jobs.

-- Weatherford signed an MoU for $2 billion of projects related to localizing oil field goods and services.

-- Dow Chemical signed an agreement to build a manufacturing facility to produce polymers for coatings and water-treatment applications, and an MoU for a feasibility study of a proposed investment in performance silicones.

-- McDermott signed a $2.8 billion MoU to deliver projects localizing goods and services along Saudi Aramco’s supply chain.

-- Honeywell signed a $3.6 billion MoU to deliver projects localizing goods and services in Saudi Aramco’s supply chain.