A group of Japanese lawmakers is looking to ramp up security cooperation with the United States and Taiwan in a bid to counter China's military buildup and growing assertiveness in the region, according to sources familiar with the plan.

The cross-party group, headed by Keiji Furuya of the ruling Liberal Democratic Party, is mulling the creation of a forum with U.S. and Taiwanese lawmakers by the end of the year to facilitate such coordination, the sources said.

The move coincides with independence-minded President Tsai Ing-wen's bid for re-election in Taiwan's presidential election in January.

As such, the envisaged trilateral parliamentary tie-up may anger China at a time when ties with Japan have been improving and ahead of a planned state visit by Chinese President Xi Jinping to the country in the spring.

China, led by the Communist Party, regards the self-ruled, democratic island as a renegade province to be reunited with the mainland, by force if necessary.

While neither Japan nor the United States has diplomatic relations with Taiwan, Furuya said, "We share fundamental values such as freedom and democracy."

"It would be highly significant if the lawmakers (among the three parties) build ties," he said.

The first meeting is likely to be held after Japan's current Diet session ends in early December, according to the sources.

Under the envisioned plan, the lawmakers will focus on ways to counter China's military buildup -- its $170 billion annual defense budget is nearly four times that of Japan and second only to the United States -- as well as its endowment of economic aid to Pacific Island nations in an attempt to draw them away from Taiwan.

In September, two Pacific Island states -- Kiribati and the Solomon Islands -- severed diplomatic ties with Taiwan in what analysts regard as a plot by Beijing to isolate Taipei.

That now leaves only 15 countries that recognize Taiwan as a sovereign entity.

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