The world's nations spent a combined $1.9 trillion (1.78 trillion euros) on their militaries in 2019, according to a report by the Stockholm International Peace Research Institute (SIPRI).

Compared to 2018, that represented an annual growth of 3.6 percent, the largest spending growth since 2010.

"Military spending has reached the highest point since the end of the Cold War," Nan Tian, a researcher at SIPRI, told AFP.

Driving the increase are the world's largest spenders, headed by the US, which spent $732 billion in 2019, a 5.3 percent increase, alone accounting for 38 percent of global spending.

2019 marked the second year of growth in US military spending after seven years of decline.

For the first time, two Asian countries were among the top three, with China and India spending an estimated $261 billion (up 5.1 percent) and $71.1 billion (up 6.8 percent) respectively.

While Chinese expenditure over the past 25 years has closely followed the country's rapid economic expansion, their investments also reflect their ambition of a "world class military".

"China has openly stated that they want to essentially compete with the US as a military superpower," Tian said.

China's ascent also in part helped explain India's rise.

"India's tensions and rivalry with both Pakistan and China are among the major drivers for its increased military spending," SIPRI researcher Siemon Wezeman said in a statement.

- Virus impact -

The world's top five spenders, which also included Russia and Saudi Arabia, together accounted for over 60 percent of total military expenditure.

According to SIPRI, other notable developments included Germany, which increased spending by 10 percent in 2019 to $49.3 billion, the largest percentual increase of all the top 15 spenders.

Germany's increased spending could in part be explained by an increased perception of threat from Russia, according to the report's authors.

While Tian noted that "military spending growth has accelerated in recent years," he also told AFP that this trend could be reversed as a result of the new coronavirus pandemic, and its economic fallout.

As the world heads for a potential global recession, Tian argued that governments will have to weigh military spending against other sectors, such as healthcare and education.

"It's highly likely that this will really have an impact on military spending," Tian said.

Looking at the historical data, that fall in spending would however likely not last, according to Tian who recalled the financial crisis of 2008, when military spending fell in subsequent years as countries, especially in Europe, imposed austerity measures.

"We could be looking at one to three years of declining spending and then an uptick again in the years to come," Tian told AFP.