LONDON — Continuing Royal Air Force precision strikes against Islamic State (IS) targets in Iraq has prompted Britain's Ministry of Defence to open negotiations with Raytheon UK to replenish stocks of the company's Paveway IV weapon.

With RAF missile and bomb strikes against IS reaching the 300 mark since the first attacks in late September 2014, the MoD said a new order to top up Paveway IV stocks is in the works.

"I can confirm that there are discussions over the replenishment of Paveway IV stocks," an MoD spokeswoman said.

Richard Daniel, the Raytheon UK CEO, told Defense News that a new order for the 500-pound-class Paveway IV is one of the potential business wins this year.

"We are certainly talking to the RAF about what their requirements are. We never comment on operations but with everything going on the British will need more and more of these weapons," Daniel said.

Nobody is willing to talk about the size of any deal for the moment.

Previously, the government placed several Paveway IV orders in the aftermath of the NATO air campaign in Libya in 2011, the largest of which was worth around £60 million (US $89.3 million).

Raytheon UK has also exported Paveway IV to the Royal Saudi Air Force where it is deployed on Tornado and Typhoon aircraft and being used against the Islamic State.

Eight RAF Tornado jets operating out of the British base at Akrotiri, Cyprus, carry the weapon along with the dual-mode Brimstone missile to provide strike capabilities against IS targets in Iraq. British Reaper remotely piloted vehicles operating from a base in the Middle East use Lockheed Martin Hellfire missiles against IS.

The MoD spokeswoman declined to give a breakdown of the weapons used by the RAF in Iraq.

Briefing reporters at the IDEX show in Adu Dhabi in February, Defence Procurement Minister Philip Dunne didn't give any figures for strikes using the British-built precision bomb but did say the smaller Brimstone accounted for close to a third of all strikes at that time.

That figure is pretty much borne out by a check of the latest air strike commentary on the MoD website for the period between March 1 and April 2.

The figures point to a total of just over 40 missiles and bombs dropped during the period.

If the commentary is accurate, Paveway IV marginally topped the list of weapons fired last month followed closely by Hellfire and then Brimstone.

During the NATO campaign against the regime of Col. Moammar Gadhafi in 2011, some air forces faced heavy criticism as their air weapon stocks fell to dangerously low levels despite it being a relatively short campaign.

While the campaign against IS is less intensive than were the Libyan strikes, the commitment of Britain and other air forces remains more open-ended, making weapon replenishment orders a likely regular occurrence.

Doug Barrie, the senior air analyst at the International Institute of Strategic Studies think tank here, says replenishing weapon stockpiles goes beyond solving the short-term needs in the Middle East.

"The broader question is whether a number of European nations, the UK included, need to go back and revisit some of their assumptions about weapon stock levels," he said.

"During the Cold War there were significant war stocks ready to tap into because of the nature of the potential conflict they could have got involved in. At the end of the Cold War, though, people understandably looked at their stock levels and thought they could cut them significantly. One of the things thrown up by Libya and other campaigns is whether they have got those stock levels right. In some cases they probably haven't," said Barrie.

The IISS analyst said it wasn't just a case of looking at numbers of weapons but also "assumptions about how much time you might have to rebuild those stocks if required."

MBDA said an arrangement it had with the British government, known as the Portfolio Management Agreement, enabled the company to respond quickly to dual-mode Brimstone requirements.

"MBDA has demonstrated our Brimstone industrial surge capability to support previous operational needs [in Libya] and, due to the Portfolio Management Agreement, we are proactively able to flex to meet our customer's changing needs," said a company spokesman

The European missile maker said it was already supplying additional dual-mode Brimstone missiles for the RAF.

"MBDA is currently supplying dual-mode Brimstone missiles, as we periodically do, to ensure our customer's operational advantage with this unique weapon is sustained. It is not appropriate to elaborate on any details of quantities or timescales," the spokesman said.

The British arm of MBDA has secured several top-up orders for dual-mode Brimstone since it was purchased as an urgent operational requirement to meet RAF needs in Iraq and Afghanistan.

Some of those additional orders have been announced but others likely haven't.

MBDA doesn't start from scratch building the dual-seeker Brimstone variant but converts missiles from an earlier large MoD order for less capable missiles.

Even so, the conversion takes between six and nine months, according to then-Defence Procurement Minister Peter Luff, announcing an order for 150 weapons in 2011.

The missile maker is currently in production with an improved Brimstone 2 version of the weapon expected to be available at the end of this year.

The MoD spokeswoman said there were no talks underway with the US at the moment for a further buy of Lockheed Martin's Hellfire missile.

Barrie reckons the MoD "might be loath to buy too many more Hellfire's because they will soon have the option to switch to Brimstone 2."

MBDA revealed last month it was studying the use of Brimstone 2 on helicopters. The company tested the man-in-the-loop weapon on a Reaper last year in a series of trials conducted in the US.

The British Army currently use Hellfire on their Apache attack helicopters.