Official sources say the state needs to keep defence spending high, despite the fact the ethnic war has ended, because of hefty installment payments on military hardware bought to fight the separatist Tamil Tigers.
Government forces crushed the rebels in May 2009, ending what had become Asia's longest-running ethnic conflict that claimed up to 100,000 lives over nearly four decades, according to UN estimates.
The highest portion of the defence budget next year in the island nation of 20 million people will go to the army.
The army will absorb just over half of the entire defence spending to maintain its 200,000 personnel, the figures show.
President Mahinda Rajapakse, who is also finance minister, is due to unveil the full 2011 budget on November 22, when he is expected to announce new revenue raising proposals to meet state expenses.Sri Lanka's fiscal deficit shot up to 9.7 percent of gross domestic product in 2009, exceeding the seven percent target set by the International Monetary Fund when it released a 2.6-billion-dollar bailout package in 2009.