BEIJING -- China's military budget will grow by about 10 per cent in the coming year, a legislative spokeswoman said Wednesday, despite slowing economic growth that fell to 7.4 per cent last year and is expected to further decline in 2015.

It would be a slightly smaller rise than last year, but would reflect the fifth year in a row of double-digit increases, bringing the total military budget to about $145 billion. The Pentagon and global arms bodies estimate actual spending may be anywhere from 40 to 50 per cent more because the budget doesn't include the costs of high-tech weapons imports, research and development, and other key programs.

The higher spending is seen as a reflection of China's growing economic might and its desire to assert itself in the region and internationally. Beijing says the bigger budgets are merely aimed at modernizing and improving conditions for the 2.3 million-member strong People's Liberation Army, the world's largest standing military.

The planned increase of about 10 per cent -- to be confirmed Thursday at the opening of the National People's Congress -- is in line with the overall increase in government spending planned for 2015, NPC spokeswoman Fu Ying told a news conference.

"China has a tougher road to travel than other large nations in terms of national defence modernization. We can only rely on ourselves for research and development of most of our military technology," Fu said. "Meanwhile, we need to ceaselessly improve conditions for our soldiers."

Fu reiterated China's position that it maintained a strictly defensive military posture and had never used "gunboats to open routes" as a means of advancing its economic and trade interests.

Despite such assurances, China's spending draws comparisons to trends among other countries in the region, many of which have been unnerved by China's rise.

Japan increased its defence budget by2.8 per cent this year to a record $42 billion, the third consecutive year of increases following 11 years of declines prior to hawkish Prime Minister Shinzo Abe's rise to power in 2012. Planes and naval vessels to counter China's growing capabilities top the Japanese military's shopping list.

Even more dramatically, India, the world's biggest arms importer in recent years, increased its spending this year by 11 per cent to $40 billion, with big increases for the navy and air force. China and India have a disputed land border and New Delhi has expressed concern about the PLA navy's growing presence in the Indian Ocean.

China's spending is still less than a third of the U.S. defence budget, a proposed $534 billion this year along with $51 billion for the conflicts in Afghanistan, Iraq and Syria. But it comes against a background of anticipated flat or falling American spending on its armed forces in coming years.

China is seeking to improve conditions for the military amid rising labour costs and competition with the private sector for top graduates in science and technology.

The need for ever-more sophisticated weaponry is increasing its costs, with the addition of an aircraft carrier combat wing and the rolling out of two prototype stealth fighters.

China's main security challenges range from its contested frontier with India high in the Himalayas to disputes over waters and islands in the South China Sea and a bitter spat with Japan over an uninhabited archipelago in the East China Sea.

New missions are also taking the PLA beyond its previous mandate to guard China's borders and prepare for any contingencies involving Taiwan, the self-governing island democracy that Beijing has pledged to take control of, by force if necessary.

Alongside its active participation in United Nations peacekeeping missions, China is now poised to pass a new anti-terrorism law that would permit it to send military forces overseas to take part in such missions if granted permission by the host nation.

However, China's forces are also seen as being hampered by political interference and top commanders have lately come under scrutiny as part of a nationwide crackdown on corruption.

Already, President Xi Jinping has overseen the arrests of two top generals, including the military's retired No. 2, Xu Caihou, and this week announced a further list of 14 top officers who are now under investigation or have been convicted of crimes such as selling ranks, embezzling funds or taking kickbacks on contracts for housing and other projects.