By Rob Taylor

CANBERRA--Australia's diplomatic juggling act in wooing Chinese investment while strengthening its military alliance with the U.S. will be tested by visits in quick succession by Chinese Premier Li Keqiang and U.S. Vice-President Mike Pence.

Mr. Li, the first premier to visit Australia in 11 years, will arrive on Wednesday for five days before traveling to New Zealand. Mr. Pence is scheduled to visit Australia next month on a date not yet announced.

The meetings will color a simmering debate in Australia over whether the country should tilt its trade and security priorities toward China, as the Asia-Pacific region's emerging power, and away from a more unpredictable and protectionist-mindedU.S. under President Donald Trump.

The visits come amid unease between the U.S. and Australia after Mr. Trump pulled the U.S. out of the regional Trans-Pacific Partnership trade pact that Canberra strongly backed and the American and Australian leaders argued over a refugee accord between the two nations. Both deals were negotiated under the Obama administration.

At stake are large economic and military ties and regional diplomatic balance. Canberra and Washington have a decadeslong security alliance and Australia hosts vital U.S. military facilities for visiting American warplanes and marines. China, meanwhile, conducted $105 billion in trade with Australia last year, nearly three times that of the U.S.

During the trip, Mr. Turnbull said he and Mr. Li would sign agreements to expand the China-Australia Free Trade Agreement and improve ties in services and innovation, as well as investment in infrastructure and other areas.Euan Graham, a senior security analyst at Australia's Lowy Institute foreign policy think tank, said Australia was unlikely to water down its security ties with the U.S. but that China would be watching opportunistically to draw Australia more closely into its economic and trade sphere.

"Any indication of fissures within main ally relationships is something that China will obviously jump upon," Mr. Graham said.

Australian Prime Minister Malcolm Turnbull, who has rejected suggestions that Australia or its neighbors face a choice between Beijing and Washington, said this week that Mr. Li's trip "highlights Australia's strong economic relationship with China and our mutual commitment to encouraging trade and investment in our region."

Chinese Vice Foreign Minister Zheng Zeguang, speaking on Tuesday, said that during a time of global economic challenges the visit "will send a positive signal to the Asia-Pacific and the whole world."

He emphasized the two nations' strong economic relationship, including those of agriculture, energy and tourism, saying the partners "have transcended and gone beyond our ideological differences." Instead, he said, "we have made every effort to emphasize cooperation and make the pie of common interest even bigger."

In contrast, when Mr. Pence visits Australia next month as part of a broader Asia tour, the government will be looking for reassurance on security and future U.S. commitment to the region, Australian officials said.

Other Asian nations are also debating their relationships between two adversarial global powers. The Philippines under President Rodrigo Duterte began to embrace China and distance itself from the U.S. even before Mr. Trump's rise. South Korea has come under increasing pressure from China over its security arrangements with the U.S. Other neighbors, such as Vietnam, remain wary of China.

Australia's relationship with the U.S. has grown more complicated since Mr. Trump became president. Polls last year showed two in three Australians opposed Mr. Trump's election, believing it would make the world more dangerous.

A former Australian envoy to Beijing, Stephen FitzGerald, drew much attention by calling in a speech this month for a reassessment of U.S. ties, saying Mr. Trump's views on trade, immigration and other issues were "an affront" to Australians now "living in a Chinese world."

Australia's Foreign Minister Julie Bishop countered that the U.S. was still the "pre-eminent global strategic power in Asia and the world by some margin," saying that China would reach its economic potential only if the country embraced democratic change. Australia, Ms. Bishop said, wanted the U.S. to shoulder an even greater role as the "indispensable strategic power in the Indo-Pacific."

In another sign of where the diplomatic ballast now rests, the recently--retired head of Australia's foreign affairs department, Peter Varghese, argued for maintaining a strong relationship with Washington. He said the U.S. alliance would survive "whatever dramas" the Trump administration brings.

"Without the alliance we would be less secure, have to pay much more for our defense and would be more vulnerable to pressure from other countries," said Mr. Varghese. Australia ultimately wouldn't be able to avoid "facing up to China's ambition to displace the U.S. as the predominant power in Asia," he said, judging it to be an ambition "at the heart of Australia's alliance with the U.S."

Te-Ping Chen in Beijing contributed to this article.

Write to Rob Taylor at rob.taylor@wsj.com

(END) Dow Jones Newswires

March 21, 2017 06:06 ET (10:06 GMT)

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