WASHINGTON (AP) — Secretary of State Antony Blinken is starting three days of talks with senior Chinese officials in Shanghai and Beijing this week with U.S.-China ties at a critical point over numerous global disputes.

The mere fact that Blinken is making the trip — shortly after a conversation between President Joe Biden and Chinese leader Xi Jinping, a similar visit to China by Treasury Secretary Janet Yellen and a call between the U.S. and Chinese defense chiefs — might be seen by some as encouraging, but ties between Washington and Beijing are tense and the rifts are growing wider.

From Russia and Ukraine to Israel, Iran and the broader Middle East as well as Indo-Pacific and trade issues, the U.S. and China are on a series of collision courses that have sparked fears about military and strategic security as well as international economic stability.

Blinken "will raise clearly and candidly our concerns" during the talks starting Wednesday, a senior State Department official said.

Here's a look at some of the key issues Blinken is expected to bring up on the trip:

RUSSIA-UKRAINE WAR

The Biden administration has grown increasingly concerned in recent months about Chinese support for Russia's defense industrial base, which U.S. officials say is allowing Moscow to overcome Western sanctions imposed after its invasion of Ukraine and resupply its military. U.S. officials say this will be a primary topic of conversation during Blinken's visit.

While the U.S. says it has no evidence China actually is arming Russia, officials say other activities are potentially equally problematic.

"If China purports on the one hand to want good relations with Europe and other countries, it can't on the other hand be fueling what is the biggest threat to European security since the end of the Cold War," Blinken said last week.

China says it has the right to trade with Russia and accuses the U.S. of fanning the flames by arming and funding Ukraine. "It is extremely hypocritical and irresponsible for the U.S. to introduce a large-scale aid bill for Ukraine while making groundless accusations against normal economic and trade exchanges between China and Russia," Foreign Ministry spokesperson Wang Wenbin said Tuesday in Beijing.

A senior State Department official said Friday that "through Chinese support, Russia has largely reconstituted its defense industrial base, which has an impact not just on the battlefield in Ukraine but poses a larger threat, we believe, to broader European security."

MIDDLE EAST TENSIONS

U.S. officials, from Biden on down, have repeatedly appealed to China to use any leverage it may have with Iran to prevent Israel's war against Hamas in Gaza from spiraling into a wider regional conflict.

While China appears to have been generally receptive to such calls — particularly because it depends heavily on oil imports from Iran and other Mideast nations — tensions have steadily increased since the beginning of the Gaza war in October and more recent direct strikes and counterstrikes between Israel and Iran.

Blinken has pushed for China to take a more active stance in pressing Iran not to escalate tensions in the Middle East. He has spoken to his Chinese counterpart, Wang Yi, several times over the past six months and urged China to tell Iran to restrain the proxy groups it has supported in the region, including Hamas, Lebanon's Hezbollah, Yemen's Houthis and Iranian-backed militias in Iraq and Syria.

Blinken told Wang in a phone call this month that "escalation is not in anyone's interest and that countries should urge Iran not to escalate," State Department spokesman Matthew Miller said of their last conversation.

The senior State Department official said Blinken would reiterate the U.S. interest in China using "whatever channels or influence it has to try to convey the need for restraint to all parties, including Iran."

TAIWAN AND THE SOUTH CHINA SEA

In the Indo-Pacific region, China and the United States are the major players, but Beijing has become increasingly aggressive in recent years toward Taiwan and its smaller Southeast Asian neighbors with which it has significant territorial and maritime disputes in the South China Sea.

The U.S. has strongly condemned Chinese military exercises threatening Taiwan, which Beijing regards as a renegade province and has vowed to reunify with the mainland by force if necessary. Successive U.S. administrations have steadily boosted military support and sales for Taipei, much to Chinese anger.

The senior State Department official said Blinken would "underscore, both in private and public, America's abiding interest in maintaining peace and stability across the Taiwan Strait. We think that is vitally important for the region and the world."

In the South China Sea, the U.S. and others have become increasingly concerned by provocative Chinese actions in and around disputed areas.

In particular, the U.S. has voiced objections to what it says are Chinese attempts to thwart legitimate maritime activities by others in the sea, notably the Philippines and Vietnam. That was a major topic of concern this month when Biden held a three-way summit with the prime minister of Japan and the president of the Philippines.

HUMAN RIGHTS AND SYNTHETIC OPIOIDS

The U.S. and China are at deep odds over human rights in China's western Xinjiang region, Tibet and Hong Kong as well as the fate of several American citizens that the State Department says have been "wrongfully detained" by Chinese authorities.

China has repeatedly rejected the American criticism as improper interference in its internal affairs. Yet, Blinken will again raise these issues, according to the senior State Department official, who added that China's self-described efforts to rein in the export of materials that traffickers use to make fentanyl have yet to yield significant results.

The two sides agreed last year to set up a working group to look into ways to combat the surge of production of fentanyl precursors in China and their export abroad. U.S. officials say they believe they had made some limited progress on cracking down on the illicit industry but many producers had found ways to get around new restrictions.

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Associated Press writer Ken Moritsugu in Beijing contributed.