Several European countries including the United Kingdom, France, and Germany, have temporarily halted arms exports to Turkey over the country's military incursion into northern Syria.

The operation, which has been ongoing for almost a week, has so far resulted in hundreds of deaths among Kurdish-led Syrian Democratic Forces (SDF), according to the Syrian Observatory for Human Rights.

But this reaction from EU countries has also directed a spotlight to the bloc's other arms trading partners — most notably Saudi Arabia, which is involved in a controversial war in Yemen.

A Saudi-led coalition has been fighting against rebels in Yemen since 2015 in a conflict that has led to the confirmed deaths or injuries of nearly 18,000 people, with the actual number believed to be higher.

Around 24.1 million people in the country are also in need of some kind of humanitarian or protection assistance, the UN Office for the Coordination of Humanitarian Affairs said in a 2018 report, calling it the worst humanitarian crisis in the world.

But despite these figures — and with the war edging close to its sixth year — many EU countries have had a somewhat delayed response when it comes to arms deals with the Saudis, while some haven't really responded at all.

So, which countries are involved?

United Kingdom

The UK didn't halt its arms exports to Saudi Arabia until June 2019, when the UK Court of Appeal found the exports licenses were unlawful because the government at the time had failed to properly assess violations to international humanitarian law and the risk to civilians.

But in late September, Trade Secretary Liz Truss said there had been three "inadvertent" breaches of the arms ban, two of which she revealed in a letter to the committee on arms exports controls, and another of which was revealed to parliament.

France

France has exported armoured vehicles to the Saudis, which Peter Wezeman, a senior researcher with the Stockholm International Peace Research Institute (SIPRI), said was "the kind of equipment that you would likely see end up either in Yemen, or on the border with Yemen, or being used with the conflict of Yemen".

In 2018, Saudi Arabia was ranked at France's second-biggest client with more than €1 billion in arms exports, a report on the country's arms exports presented to parliament showed.

In May, French President Emmanuel Macron said he "acknowledges" the sale of French weapons to Saudi Arabia, with assurances that they are "not used against civilians".

French defence minister Florence Parly has also said the country's government had not recently sold any arms that were being used in Yemen, but leaked documents released earlier this year suggest otherwise.

Germany

The German government stopped exporting arms to Saudi Arabia in October 2018 after the killing of Washington Post journalist Jamal Khashoggi at the Saudi consulate in Istanbul.

Its ban on exports is to last until March 2020, which is an extension from the first deadline, which passed last month.

But despite this position, the memorandum does not include other parties that are fighting as part of the Saudi-led coalition, leading to criticisms that the German government is still contributing arms that are, in turn, used in the Yemen war.

Spain

In 2018, Spain announced that it was suspending its arms exports to Saudi Arabia, citing what it says could be implied as "the direct use of this type of armament against a civilian population".

However, the Spanish government backtracked on this decision just a few weeks later after the Saudis threatened to scrap a construction deal that would see thousands of people in southern Spain lose their jobs. They haven't changed their position since.

Why would EU countries halt arms to Turkey for the conflict, but not to Saudi Arabia for the same reasons?

There are a number of reasons, but two in particular stand out: business and alliances.

France, Germany, the United Kingdom, Spain and Italy are all among the world's top ten biggest exporters of arms, while Saudi Arabia is also the world's biggest importer of arms.

Turkey, in comparison, is the 13th biggest importer of arms.

Between 2013-17, the largest arms supplier to the Saudis was by far the US (61%).

But this was also followed by the UK (23%), France (3.6%), Spain (2.4%), Switzerland (1.8%), Germany (1.8%) and Italy (1.5%) respectively, according to SIPRI data.

So — have countries been more reluctant to sanction one of their biggest clients because of economic reasons? Not necessarily, according to Wezeman.

He said: "You could ask whether Turkey is less of an important market than Saudi Arabia, but this is not the case for Germany, at least, for which Turkey has been (an important client) for a long time."

An alternative way to look at it could also be that these EU countries have long held alliances with the Saudis — but not with the Saudi enemy in Yemen, ie: the Houthis.

But with Turkey's incursion into northern Syria against Kurdish-led forces, there are two European allegiances at stake.

Turkey, as a NATO member, is an obvious example. However, the West also holds allegiances with the Kurds, who were a crucial partner in the fight to defeat the Islamic State.

For Wezeman, this partnership with the Kurds would have definitely played a role in the decision from EU countries to rapidly halt arms exports.

But, he adds, Turkey's geographical proximity to Europe could also have affected this.

"The fight against IS is particularly important for Europe, whereas what happens in Yemen has no immediate impact, and doesn't lead to refugees or potential terrorists coming to Europe."

He later highlighted the role of morality and adherence to international humanitarian rules that do play a role in a country's decision to pause arms trade.

"In Germany, there is a significant arms industry, and they were keen to get a substantial arms contract with Saudi Arabia.

"They had a very good chance of selling tanks, and, in the end, the German government took the decision not to take those steps."

But in general, political perspectives on arms trade can differ from country to country.

Moral considerdations, for instance, play a smaller role than business in countries such as France and the UK, according to Wezeman — unlike in Germany, Sweden and Norway, where you might expect to find the opposite.

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