By Michael Martina

BEIJING (Reuters) - China has become the world's fifth-largest arms exporter, a respected Sweden-based think-tank said on Monday, its highest ranking since the Cold War, with Pakistan the main recipient.

China's volume of weapons exports between 2008 and 2012 rose 162 percent compared with the previous five-year period, with its share of the global arms trade rising from 2 percent to 5 percent, the Stockholm International Peace Research Institute (SIPRI) said.

China replaces Britain in the top five arms-dealing countries between 2008 and 2012, a group dominated by the United States and Russia, which accounted for 30 percent and 26 percent of weapons exports, SIPRI said.

"China is establishing itself as a significant arms supplier to a growing number of important recipient states," Paul Holtom, director of the SIPRI Arms Transfers Programme, said in a statement.

The shift, outlined in SIPRI's Trends in International Arms Transfers report, marks China's first time as a top-five arms exporter since the think-tank's 1986-1990 data period.

Chinese Foreign Ministry spokesman Hong Lei, asked about the report, said China was a responsible arms exporter which strictly adhered to international law.

"On arms exports, China sticks to three principles. First, that it is conducive to the recipient country's justifiable self-defense needs. Second, it does not damage regional and global peace, security and stability. Third, it does not interfere in other countries' internal affairs," he told reporters.

Now the world's second-largest economy, China's rise has come with a new sense of military assertiveness with a growing budget to develop modern equipment including aircraft carriers and drones.

At the Zhuhai air show in southern China in November, Chinese attack helicopters, missiles, unmanned aerial vehicles and air defenses were on public show for the first time.

PAKISTAN, MYANMAR, BANGLADESH

SIPRI maintains a global arms transfers database base that tracks arms exports back to the 1950s. It averages data over five-year periods because arms sales vary by year.

"Pakistan - which accounted for 55 percent of Chinese arms exports - is likely to remain the largest recipient of Chinese arms in the coming years due to large outstanding and planned orders for combat aircraft, submarines and frigates," SIPRI said.

Myanmar, which has been undergoing fragile reforms that the United States thinks could help counter Beijing's influence in the region, received 8 percent of China's weapons exports.

Bangladesh received 7 percent of the arms while Algeria, Venezuela and Morocco have bought Chinese-made frigates, aircraft or armored vehicles in the past several years.

China does not release figures for its arms sales.

Germany and France ranked third and fourth on the arms exporter list. China followed only India in the acquisition of arms, though its reliance on imports is decreasing as it ramps up domestic production.

After decades of steep increases in military spending and cash injections into domestic contractors, experts say some Chinese-made equipment is now comparable to Russian or Western counterparts, though accurate information about the performance of Chinese weapons is scarce.

China faces bans on Western military imports, dating back to anger over its crushing of pro-democracy protests in and around Tiananmen Square in 1989. That makes its domestic arms industry crucial in assembling a modern military that can enforce claims over Taiwan and disputed maritime territories.

China has faced off recently with its Southeast Asian neighbors and Japan over rival claims to strings of islets in the South China Sea and East China Sea, even as the United States executes a so-called pivot towards the Pacific.

(Additional reporting by Sui-Lee Wee; Editing by Robert Birsel)