China will raise its defense budget by around 10 percent this year, its slowest increase in five years.

The number will put China's military spending at some 890 billion yuan ($145 billion). The US military has budgeted $577 billion in 2015, Reuters reported.

"The truth is a gap remains between China's armed forces [and foreign counterparts] in terms of overall military equipment," Fu Ying, spokeswoman for the annual session of the country's top legislature, told reporters on Wednesday, a day ahead of the Third Session of the 12th National People's Congress (NPC).

Fu said funds are needed to modernize China's national defense and army.

This year's increase is the lowest in five years. China's defense budget rose by 12.2 percent in 2014 to 808.2 billion yuan.

Yin Zhuo, a military expert from the Chinese Navy Advisory Committee for Informatization, said China continues to feel the need to build its military. 

"There remains a wide gap between China's military strength and that of the US, despite an increase in defense spending. As China's overseas interests expand, the strength of the country's naval forces still cannot adequately protect China's interests abroad," Yin said.

Han Hua, an associate professor at Peking University, said the smaller increase in defense spending is consistent with the country's lower economic growth target.

The Chinese economy grew 7.4 percent in 2014, the weakest annual expansion in 24 years.

China's military expenditure in 2014 accounted for less than 1.5 percent of GDP, which is not only well below that of major countries, but also less than the world average of 2.6 percent, Chinese foreign ministry spokesperson Hua Chunying said in February.

Fu also stressed that China's military policy is defensive in nature and that the principle is "clearly defined in the country's Constitution."

The country's past achievements in reform and opening up come not from "cannons and warships" but from mutually-beneficial cooperation, Fu said, adding that China will stick to the path of peaceful development.

"This year could mark a turning point in China's defense budget growth. We are about to complete the basic military infrastructure and stabilize salaries, which form the bulk of the budget," a military expert, who requested anonymity, told the Global Times.

Several deals are expected to be made in 2015 to beef up China's military, including the purchase of Russia's S-400 surface-to-air missile systems and Sukhoi SU-35 jet fighters, the expert said.

Aside from strengthening national defense, Han pointed out that China is also offering security products to the world, including anti-piracy escorts and aid to rebuild Afghanistan. "China is capable of and willing to help the world, but it is just the start. Some countries might not welcome China's security products because they consider a rising China a threat."

Shanghai-based military expert Ni Lexiong is confident that the nation's anti-corruption campaign would have an impact on military budget transparency. "With less waste, our combat effectiveness will be enhanced. More money will be spent on combat training and military maneuvers."

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