China has eased ahead of Germany and France to become the world's number three arms exporter after the United States and Russia, a Stockholm-based think-tank said Monday.

The volume of the multi-billion dollar world arms trade rose 16 percent during the period 2010 to 2014 over the previous five years, the Stockholm International Peace Research Institute added in its annual report.

The figures show that "the United States has taken a firm lead" with 31 percent of global exports of conventional weapons, SIPRI said, with Russia in second place at 27 percent.

The next three arms exporters are far behind with about five percent each, and China is only slightly ahead of fourth-ranked Germany and fifth-ranked France.

Three Asian countries accounted for more than two-thirds of Chinese exports, with Pakistan buying 41 percent of the total, followed by Bangladesh and Myanmar. Beijing also had 18 client nations in Africa during the period.

Russia's top client was India -- the world's leading arms importer -- with 70 percent of its purchases coming from Russia.

The United States had the most diverse clientele. South Korea, its top client, accounted for only nine percent of total US business.

Among leading suppliers, China's sales were up 143 percent compared to the previous five-year period. Ukraine and Russia also saw surges in exports, while those of Germany and France declined.

"China is always prudent and responsible in arms exports," foreign ministry spokesman Hong Lei told reporters.

"We insist on the principles that it (arms exports) should be conducive to the legitimate self-defence capability of the recipient country, not impair international and regional peace and stability, and not interfere in the domestic affairs of other countries."

The data reflects the volume of arms deliveries, not the financial value of the deals, SIPRI notes.

Among importers, India was far ahead of second- and third-placed Saudi Arabia and China, purchasing some 15 percent of the total volume -- despite ranking 9th in terms of military budgets -- compared with five percent each for the next two.

According to the latest SIPRI figures, the US retains the world's largest military budget at $640 billion (608 billion euros), far ahead of China ($188 billion) and Russia ($87.8 billion).

African arms imports shot up 45 percent in the period, SIPRI found. "Algeria was the largest arms importer in Africa, followed by Morocco, whose arms imports increased 11-fold," it said.

"Cameroon and Nigeria received arms from several states in order to fulfil their urgent demand for weapons to fight against the militant Islamist group Boko Haram," SIPRI added.

While the arms trade has been on the rise for the past decade, the volume remains about one-third below its post-war peak reached in the early 1980s.