The global arms industry was worth a staggering $100 billion (£74bn) in 2017 and is set to surpass that figure this year. As Western weapons sales to Saudi Arabia come under scrutiny following the bombing of civilians in Yemen and the murder of journalist Jamal Khashoggi, we take a look at the countries that make the most money from international heavy weapon exports.

The Stockholm International Peace Research Institute (SIPRI) compiles the definitive database of global heavy weapons transfers. SIPRI measures the value of these weapons exports using a common unit called trend-indicator value (TIV), expressed in US dollars at constant 1990 prices. We've ranked each country based on the SIPRI figures for 2017, but have added total arms exports figures in current US dollars where available.

The world's 10th biggest exporter of heavy weapons, Italy sold $660 million (£508m) worth at constant 1990 prices last year according to SIPRI. The Italian government hasn't released total arms sales data for 2017, but the nation's weapons exports have been on the rise.

Leonardo, formerly Finmeccanica, is Italy's largest defence company. The Rome-headquartered firm, which is partly owned by the Italian government, reported bumper revenues of $13.1 billion (£10.2bn) last year. Other major players include Beretta, Benelli and Fincantieri.

Over the past five years, Italy's biggest client has been the UAE, which accounted for 12% of all arms sales, followed by Turkey and Algeria. Italian weapons exports to the UAE and Saudi Arabia have drawn particular criticism. Last December, the New York Times revealed that the Saudi-led coalition had used Italian-made bombs to target civilians in Yemen.

Spain's heavy weapons exports last year amounted to $814 million (£630m) at constant 1990 prices, while government-released figures show total arms sales hit $4.9 billion (£3.8bn) at current prices, an increase of 7.3% from 2016.

The key defence suppliers in the country, which include state-owned shipbuilder Navantia and Indra, produce everything from combat land vehicles and military tankers to transport aircraft and state-of-the-art weapons systems.

Germany is Spain's number one customer and accounts for 73% of all arms exports. Spain recently cancelled a deal to supply Saudi Arabia, it's next biggest client, with 400 laser-guided bombs, only to make a U-turn on its decision and proceed with the sale. Last year, the Spanish government blocked sales to Israel, China and Myanmar.

Last year, China exported $1.1 billion (£851m) worth of heavy weapons at constant 1990 US dollar prices. Though its international arms sales fell in 2017 compared to the previous year, China's military exports have risen by 38% over the past five years.

Defence companies in the country are entirely state-owned. China South Industries Group (CSGC) is the nation's largest, followed by the Aviation Industry Corporation of China (AVIC) and Norinco.

China sells the bulk of its weaponry to countries in Asia. Over the past five years, Pakistan has been its leading client, accounting for 35% of all arms exports. The runner-up Bangladesh accounted for 19%.

Next up is the Netherlands. The EU nation's heavy weapons exports last year totalled $1.2 billion (£928m) at constant 1990 US dollar prices, a massive increase compared to 2016 when the figure was just $471 million (£364m).

The country's chief defence companies, which include Thales Nederland and the Damen Group, excel in cutting-edge naval defence systems, combat land vehicles and military aircraft.

Jordan is the Netherlands' main client. Controversially, the Middle Eastern nation, which is part of the Saudi-led coalition against Yemen, acquired 15 Dutch F-16 aircraft last year. The next most important customer is Indonesia, followed by the US. Both countries have bought Damen naval ships.

Last year, the UK exported heavy weapons that amounted to $1.2 billion (£928m) at constant 1990 US dollar prices. Research from the Defence Security Organisation shows that British defence companies secured exports valued at $11.6 billion (£9bn) at current prices in 2017.

BAE Systems is the UK's leading defence company by a long-shot. In fact, the firm, which turned over $23.7 billion (£18.3bn) last year, is one of the biggest arms manufacturers on the planet. Other top British defence companies include Britten-Norman and Cobham.

Over the past five years, Saudi Arabia has been the UK's biggest customer, accounting for 49% of all arms sales. Last July, the UK's High Court ruled that arms sales to Saudi are lawful, but the Campaign Against Arms Trade (CAAT) has been given permission to appeal the ruling. The court date is set for April 2019 and could result in a blanket ban.

The leading arms exporter in the Middle East, Israel sold $1.3 billion (£1bn) worth of heavy weapons at constant 1990 US dollar prices last year. Total arms sales surged in 2017, hitting $9 billion (£7bn) at current prices, up from $6.5 billion (£5bn) in 2016.

Israel Aerospace Industries (IAI) is the country's most prominent defence company. The firm reported revenues of $3.5 billion (£2.7bn) last year. Hot on its heels, Elbit Systems comes a close second with an annual turnover of $3.4 billion (£2.6bn).

Last year, 58% of Israel's international arms sales were to countries in Asia, primarily India, which secured a $2 billion (£1.6bn) contract with IAI for advanced Barak 8 air defence systems. Other key clients of Israel include Azerbaijan and Vietnam.

Germany's heavy weapons exports hit $1.7 billion (£1.3bn) at constant 1990 US dollar prices last year according to SIPRI. Government figures show the country approved $7.1 billion (£5.5bn) worth of arms exports in 2017 at current prices, a drop of 9% from 2016.

Pan-European defence company Airbus has a strong presence in Germany and is the largest firm of its kind in the country. Other key companies range from warship builder ThyssenKrupp to armoured vehicle specialist Rheinmetall and Heckler & Koch, a major gunmaker.

Over the past five years, South Korea has been Germany's premier client, accounting for 14% of all arms sales, followed by Greece and Israel. Unlike its counterpart in the UK, the German government has banned new arms exports to Saudi Arabia and other countries engaged in the Yemeni conflict.

Last year, France's heavy weapons exports represented $2.2 billion (£1.7bn) at constant 1990 USD prices. The country's Ministry of the Armed Forces recorded $8 billion (£6.2bn) worth of arms sales at current prices in 2017, a drop of almost half from the previous year.

France's major defence companies include Thales Group and Dassault Aviation, which was responsible for boosting the country's defence exports in 2015 and 2016, when it sold a number of Rafale fighter jets to Egypt, Qatar and India.

Over the past five years, France's main client has been Egypt, while countries in the Middle East dominated in 2017. Despite criticism over the role of these countries in the Yemeni Civil War, France's exports to the UAE and Kuwait skyrocketed last year.

The world's second-largest dealer of arms, Russia exported $6.1 billion (£4.7bn) worth of heavy weapons at constant 1990 US dollar prices last year, while official figures put total Russian arms exports at $15 billion (£11.6bn) at current prices in 2017.

Almaz-Antey, which is owned by the state, is Russia's largest defence firm. The company reported arms sales of $9.1 billion (£7.1bn) last year. Other major defence contractors in the country include United Aircraft Corporation and Russian Helicopters.

Russia's foremost client over the past five years has been India, which accounted for 35% of all arms sales, followed by China and Vietnam. The country's most questionable customers include the brutal Syrian regime and pro-Russian separatists in the Ukraine.

Eclipsing all its rivals, the USA is the world's leading heavy weapons exporter. Last year, the country sold $12.4 billion (£9.6bn) worth at constant 1990 US dollar prices. Total arms exports at current prices last year soared to $41.9 billion (£32.5bn), up 20% from 2016.

Needless to say, the world's largest defence company is American. Lockheed Martin reported revenues of $51 billion (£39.6bn) last year. Raytheon, Northrop Grumman and General Dynamics are other big players.

Saudi Arabia is the USA's biggest client, accounting for 18% of all sales over the past five years. Ignoring widespread opposition, President Trump agreed a colossal $350 billion (£272bn) deal last year to supply the Saudis with arms over the next decade.