(CNN) Over the last few years China has made a series of ambitious military reforms and acquired new technology as it aims to improve its ability to fight regional conflicts over places like Taiwan, according to a new report from the US Defense Intelligence Agency .

"Beijing's longstanding interest to eventually compel Taiwan's reunification with the mainland and deter any attempt by Taiwan to declare independence has served as the primary driver for China's military modernization," said the agency's report, titled "China's Military Power."

The report, which was published Tuesday, added that "Beijing's anticipation that foreign forces would intervene in a Taiwan scenario led the (People's Liberation Army) to develop a range of systems to deter and deny foreign regional force projection."

Earlier Tuesday in Beijing, China made plain to the US military that it is will countenance no interference on Taiwan, according to a report on the Chinese military's English-language website

"If someone tries to split Taiwan from China, the Chinese military will do whatever it takes to safeguard national reunification, national sovereignty and territorial integrity," Gen. Li Zuocheng, a member of China's Central Military Commission, told the US chief of naval operations, Adm. John Richardson, who is on a four-day visit to China.

The US DIA report estimates that Chinese spending on its armed forces "probably exceeded $200 billion" in 2018, "a threefold increase since 2002."

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In a written introduction accompanying the report, the Defense Intelligence Agency's director, Lt. Gen. Robert Ashley, wrote that China has used a variety of means to acquire advanced technology to bolster its military capabilities despite some countries attempting to limit its access to that technology over international concerns about Beijing's human rights policies.

"China shifted funds and efforts to acquiring technology by any means available. Domestic laws forced foreign partners of Chinese-based joint ventures to release their technology in exchange for entry into China's lucrative market, and China has used other means to secure needed technology and expertise," Ashley said.

While the report acknowledges that China spends significantly less on defense than the some $700 billion invested by the US in 2018, it says Beijing enjoys an advantage due to the fact that "China has not had to invest in costly R&D of new technologies to the same degree as the United States."

"Rather, China has routinely adopted the best and most effective platforms found in foreign militaries through direct purchase, retrofits, or theft of intellectual property. By doing so, China has been able to focus on expediting its military modernization at a small fraction of the original cost," it said.

'Most modern weapon systems in the world'

China is "on the verge of fielding some of the most modern weapon systems in the world. In some areas, it already leads the world," Ashley wrote.

A senior defense official said the US was concerned that China's increased capabilities may lead its military commanders to advise its political leaders that they were confident of military success with regard to a campaign against Taiwan.

"The biggest concern is that they are going to get to -- they are getting to a point where the PLA leadership may actually tell Xi Jinping that they are confident in their capabilities," the official said, referring to China's leader.

The report notes that the vast majority of China's missile arsenal is capable of hitting Taiwan while also pointing out that Beijing has developed new weapons systems like the H-6 bomber armed with CJ-20 cruise missiles, which it says is capable of striking areas farther afield, such as US military installations on Guam.

It says, "China has built or acquired a wide array of advanced platforms," including submarines, major surface combat ships, missile patrol craft, maritime strike aircraft and land-based systems that employ new, sophisticated anti-ship cruise missiles and surface-to-air missiles.

"China also has developed the world's first roadmobile, anti-ship ballistic missile, a system specifically designed to attack enemy aircraft carriers," it says.

"China's leaders hope that possessing these military capabilities will deter pro-independence moves by Taiwan or, should deterrence fail, will permit a range of tailored military options against Taiwan and potential third-party military intervention," the report said.

Earlier this month Xi called on Taiwan to reject independence and embrace "peaceful reunification" with China in a conciliatory speech that nevertheless took a hard line on the self-governing island's political sovereignty and freedoms.

And the Chinese leader added that "we make no promise to renounce the use of force. We reserve the option for all the necessary means."

In response to Xi's speech, Taiwanese President Tsai Ing-wen said the island will "never accept" a "one country, two systems" arrangement with China.

While the report says China has increased its military footprint in the South China Sea and has placed additional military facilities on man-made islands there, the Pentagon assesses that China is seeking to avoid a conflict.

"I think both sides have managed to operate professionally. And we have -- it's not in the Chinese interests for a crisis to spiral in the South China Sea. I think that they are fairly comfortable with the progress they've made in building out this infrastructure down there, and then working on negotiations with the other claimant states over a longer term," the senior defense official said.

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During his China visit, Adm. Richardson said the US Navy would continue to send warships wherever international law allows, something the Pentagon says when undertaking so-called "freedom of navigation" operations near Chinese-claimed territory in the South China Sea.

"The US Navy will continue to conduct routine and lawful operations around the world, in order to protect the rights, freedoms and lawful uses of sea and airspace guaranteed to all," Richardson said in a China-datelined story posted on the US Navy's website.

He also called on China to avoid dangerous maneuvers during those US operations.

"It important for all military, law enforcement, and civilian vessels and aircraft, including those in the PLA Navy, the Chinese Coast Guard, and the People's Armed Forces Maritime Militia, to operate in a safe and professional manner, in accordance with international law," Richardson is quoted as saying. "Consistent operations and behavior are critical to preventing miscalculation."

Last fall, the Chinese destroyer Lanzhou came within 45 yards (41 meters) of the guided-missile destroyer USS Decatur near the Spratly Islands in an encounter the US called "unsafe."