BEIJING — The Chinese military budget for 2015 will be about 10 percent bigger than last year’s, a senior Chinese official said on Wednesday, meaning that such spending is growing at a pace faster than the overall growth rate of the Chinese economy.

The estimate was given in Beijing by Fu Ying, a veteran diplomat who is the spokeswoman for the National People’s Congress, China’s legislature, whose annual meeting begins this week. Ms. Fu said at a news conference that the military budget’s precise numbers would be announced Thursday, along with other budget outlays that will later be formally approved by the legislature.

A 10 percent increase would put the 2015 military budget around $145 billion, making China the world’s second-largest military spender, though still far behind the United States, which spends more on its armed forces than the next eight countries combined.

…China’s “defense budget increases have always outpaced the growth in G.D.P.,” said Richard A. Bitzinger​, a senior fellow at ​the S. Rajaratnam School of International Studies at Nanyang Technological University in Singapore​ who has studied China’s military spending patterns.

“But this is the first time when the gap could be really, really big,” Mr. Bitzinger said. “That is, if the economy only grows by, say, 6 percent, but the defense budget grows by 10 percent, that’s a really sizable difference. It demonstrates that the Chinese leadership is committed to increasing defense spending, no matter what.”