The US is planning to sell 20 cargo aircraft and five refuelling planes to Saudi Arabia in a deal worth $6.7bn.

The contractors involved in the deal are Rolls Royce, Lockheed-Martin and GE Aviation Systems. The sale will involve the purchase of associated equipment, parts, training and logistical support, according to a statement from the US Defence Security Cooperation Agency.

Saudi Arabia is looking to purchase the 20 C-130J-30 aircraft and the KC-130J refuelling aircraft in order to “sustain its aging fleet”, according to the US agency.

The proposed sale will also contribute to the “foreign policy and national security of the US by helping to improve the security of a friendly country that has been, and continues to be, an important force for political stability and economic progress in the Middle East”, the agency adds.

Notice of the potential sale has been given to the US Congress, and the conclusion of the deal is pending final Congress approval.

The announcement of the sale comes after a visit by the UK prime minister David Cameron to the Gulf where he met with the governments of both Saudi Arabia and the UAE to encourage the sale of Typhoon fighter jets.