PARIS — An acquisition of secondhand Super Hercules C-130Js flown by the British Royal Air Force was one of the options considered by France, which seeks to buy four C-130 transport planes to boost support for troops deployed across sub-Saharan Africa, two defense sources said.

The Direction Générale de l'Armement procurement office "raised at the start of December" the option, which sparked some surprise, a French defense specialist said. Britain, which was launch customer for the Super Hercules, is looking to sell the first 10 acquired and hold on to the remaining 14 planes.

"The British C-130Js are an option for France," said US Army Col. John "Walt" Kennedy, chief of the Office of Defense Cooperation, here. The systems, including avionics, on those early models will need to be upgraded.

A DGA spokesman declined comment.

On Tuesday, US officers in Washington briefed DGA officials, in Washington on Tuesday DGA officials who sought clarification on the offer of four C-130Js, announced last month by the US Defense Security Cooperation Agency. The US Air Force has offered an accelerated delivery schedule.

A ministerial decision on the C-130 is expected to be taken in the next two weeks, following the US briefing.

The US technical briefing set out in detail the elements of the offer, which carried athe maximum price of $650 million. That figure sparked initial French concern as it far exceeded the €330 million (US $360.9 million) earmarked for the planned C-130 acquisition.

That "top price" of $650 million covered clearance for future upgrades and was intended to speed up their delivery to France.

"As was set out in the [strategic defense and security review] last month, the UK will upgrade and extend the life of some of our C-130J Hercules aircraft, ensuring they can continue to support operations around the globe," said a British Ministry of Defence spokesman.

"Some of the aircraft will be surplus to this and retired from service over the next few years, and we are currently exploring options for their disposal."

The UK is expected to retire six of the RAF's short fuselage C-130J Mk5s on Dec. 31, 2016, and a further four on March 31, 2017. That schedule reflects the expected entry into service of the Airbus A400M transport with the RAF.

The RAF plans to retain the 14 long fuselage C-130J Mk4s, extending the operational life to 2030 from 2023.

The French Army is eager to receive the C-130, as troops are deployed at great distance in Sahel sub-Saharan Africa, and the transport planes would fly a full tactical mission, dropping troops and cargoes by parachute, the French source said.

Two of the C-130s would be capable of inflight refueling for helicopters, which fly combat search and rescue and support special operations forces.

Airbus Defence & Space is developing a hose and drogue refueling kit for the C-235 and C-295 transports, Airbus Defence & Space is working on fixing a hose and drogue for on the C-235 and C-295 transports, while looking to resolve aerodynamic problems on the A400M for refueling helicopters.

Andrew Chuter contributed to this report from London