He said that in the case of conflict with Iran, the Emirates would need to protect its people and oil supplies that pass through the Strait of Hormuz.
Mark Bromley, from Sipri, told Al Jazeera the UAE may be increasing its military spending due to high prices in oil.
"States go through periods of consolidation and modernisation with their military," he said.
"It so happens that the UAE is going through a rather ambitious programme of military modernisation.
"In terms of the 'why' we can point to the recent rise in global world oil prices which is of course funding these purchases.
"What we'll see in the future is how these plans are affected by the fall in world oil prices. To date it appears the UAE is relatively unconcerned by that," he said.
The institute also revealed that the volume of weapons being exported to the Middle East has risen by more than a third in the past four years.
Sipri warned that this trend threatens to destabilise the region further.
Pieter Wezeman, a researcher for the institute, said: "While we are a long way from the levels [of imports] reached in the early to mid-1980s, this is still a worrying trend in a region beset by multiple sources of potential conflict and limited intergovernmental trust and transparency".
Sipri found that Israel was the second largest receiver of arms in the Middle East, with 22 per cent of the region's imports, followed by Egypt with 14 per cent.
Iran accounted for only five per cent of transfers to the Middle East for 2004 to 2008.