Kuwait will buy 28 Boeing F/A-18 Super Hornets to replace a fleet of earlier versions of the US fighter jets, a top official said Monday.

The value of the deal is not expected to exceed $5 billion, the KUNA state news agency reported the head of armament and procurement at Kuwait's defence ministry as saying.

Major General Lafi al-Azemi said the deal stipulates the supplier will re-purchase the old Hornet fighter jets from Kuwait.

The US State Department this month said it has authorised the deal, as well as the sale of 72 F-15 Strike Eagle jets to Kuwait's Gulf neighbour Qatar at an estimated value of $21 billion.

In April, Kuwait signed a contract with Italy's Finmeccanica for the purchase of 28 Eurofighter Typhoon warplanes for under eight billion euros ($8.5 billion).

Kuwait's parliament in March approved spending an additional $500 million as an advance payment for the jets.

That funding came on top of $10 billion additional defence spending already approved by parliament in January to upgrade the country's military.

The emirate is a member of the US-led coalition bombing Islamic State group targets in Syria and Iraq, and is also taking part in a Saudi-led coalition pounding Iran-backed rebels in Yemen.

Last year, it bought 24 Caracal military tactical transport helicopters and French light armoured vehicles.