The volume of weapons exported to the Middle East has risen sharply in the last four years, threatening to destabilize the volatile region further, a leading Swedish think tank warned Monday. The Stockholm International Peace Research Institute said arms exports to the Middle East increased 38 percent in the period 2004 to 2008, compared with 1999 to 2003. The United States supplied most of the arms although major shipments also came from France. The United Arab Emirates was the biggest importer of weapons in the region - and the third biggest in the world, after China and India, SIPRI said in a report on global arms transfers. In the 2004-2008 period, the UAE bought 80 F-16E combat aircraft from the US and 50 Mirage 2000-9 fighters from France, it said. "This is of course a big concern in a region where we see a lot of tension and full-out conflicts," SIPRI researcher Pieter Wezeman told The Associated Press. He warned that growing arsenals in the Gulf could trigger a response from Iran and encourage it to pursue nuclear weapons. "When Saudi Arabia and the United Arab Emirates increase their arsenals there is a risk that Iran will feel even more threatened and marginalized than it already is," he said. "This should be very much taken into account when countries decide to supply these countries with weapons." During the four-year period, the UAE accounted for 34 percent of the arms imports in the Middle East. Israel accounted for 22 percent and Egypt 14 percent. Only 5 percent of the arms transfers to the region went to Iran, the report said. "Iran has not been able to, or not been willing, to procure the same volumes of weapons as its neighbors," Wezeman said. "One has to wonder if its capability is not very limited, in fact." The United States remained the world's biggest exporter of arms in 2004-2008, with a 31 percent share of the global market, down from a 35 percent share in the previous four years. More than one-third of the US exports went to the Middle East, including some 207 combat aircraft and more than 5,000 guided bombs, SIPRI said. Russia's share of the export market fell to 25 percent from 26 percent, while Germany increased its arms export during the period to 10 percent of the global market from 7 percent previously. China remained the biggest importer of weapons, accounting for 11 percent of all imports between 2004 and 2008, compared with 12 percent in the four years prior to that. In total, the volume of global arms transfers between 2004 and 2008 increased by 21 percent compared with the previous four years. SIPRI also said there are some signs of countries delaying or canceling purchases as a result of the global financial crisis, but added it is too early to confirm the trend.