GEOFF BENNETT: President Trump this week spoke with Chinese leader Xi Jinping, and the Chinese government said Xi outlined what it called China's principled position on Taiwan.

The self-governing democracy of 23 million residents has never been part of communist China, but Beijing considers it a breakaway province.

Nick Schifrin recently sat down with Taiwan's deputy foreign minister at the Halifax International Security Forum to talk about the relationship with the U.S.

and why Taiwan is so focused on the fate of Ukraine.

NICK SCHIFRIN: Ukraine is fighting what it considers an existential battle, on the front line an in Geneva conference rooms.

And even those half-a-world away are watching, for they too face a much larger neighbor challenging their sovereignty.

CHEN MING-CHI, Taiwanese Deputy Foreign Minister: We don't want to have the aggressor having their way.

So we have to work together to support this whole cause.

That's very important for us.

NICK SCHIFRIN: Chen Ming-chi is Taiwan's deputy foreign minister.

We spoke this weekend at the Halifax International Security Forum just as the U.S.

pushed Kyiv to agree to a U.S.-drafted peace plan.

CHEN MING-CHI: That plan have global implications.

We are watching that closely.

In Taiwan, I think the most important thing is to strengthen our defense capabilities, so work with our allies, work with our like-minded partners, so as to provide better deterrence.

It's better to deter any aggressor beforehand, rather than in the middle of the prolonged war.

NICK SCHIFRIN: President Trump has said repeatedly that Xi Jinping has promised not to invade Taiwan during Trump's term.

Has the U.S.

ever communicated that to Taipei formally?

CHEN MING-CHI: We don't make any speculation on that.

We don't base our defense idea, concept on any empty promise.

NICK SCHIFRIN: China's People's Liberation Army has launched one of the fastest military modernizations in world history.

The U.S.

says the buildup is custom-designed to prevent U.S.

forces to come to Taiwan's rescue, as demonstrated in these propaganda videos, and to be able to invade Taiwan by 2027.

CHEN MING-CHI: We have to face two situations.

One is a D-Day situation.

The other one is a day-to-day situation.

NICK SCHIFRIN: Invasion or pressure?

CHEN MING-CHI: Yes.

So we have to deal with both.

If we fail to meet the challenge from the air, on the water, our people will lose confidence in the -- our own defense.

But we have to invest.

We have to strengthen that part.

NICK SCHIFRIN: For Taiwan, U.S.

weapons have long been essential.

Last week, the Trump administration approved the first weapons sale of this term, $700 million of the same air defense system that protects Washington.

And the week before, the U.S.

approved $330 million worth of aircraft parts.

But the Trump administration has so far chosen to sell Taiwan's military new weapons and parts, rather than draw down from U.S.

stocks to deliver them faster.

It also recently downgraded U.S.-Taiwan defense talks.

And, this year, President Lai Ching-te did not transit the U.S., as his predecessor did during the first year of the first Trump administration.

Do you fear that President Trump is sacrificing support for Taiwan in order to hold out for a deal with Beijing?

CHEN MING-CHI: Not at all.

We are very solid about our bilateral relations in terms of security.

Of course, trade-wise, it's another issue.

Your president is a tough negotiator, and ours is -- also have to protect our own interests.

NICK SCHIFRIN: The U.S.

is threatening to tariff Taiwanese-built semiconductors, the world's most advanced.

And, right now, U.S.

tariffs on Taiwan's exports are still 20 percent.

That's a threat to Taiwan's economy, just as the U.S.

demands Taiwan spend more on defense than Taiwan says it's capable of.

But Taiwan recently got a big boost from Japan's new prime minister, Sanae Takaichi who earlier this month said a Chinese assault on Taiwan would lead to a Japanese response.

SANAE TAKAICHI, Japanese Prime Minister (through translator): If China were to deploy battleships and involve the use of force, I believe this could be deemed a situation threatening Japan's survival.

NICK SCHIFRIN: China's consul general in Osaka, Japan, posted on X -- quote -- "We have no choice but to cut off that dirty neck that has lunged at us."

It was later deleted.

But China's foreign minister said Takaichi had crossed a red line.

And on yesterday's call between Xi Jinping and President Trump, Xi outlined China's -- quote -- "principled position" on Taiwan.

It was the first time a Chinese leader framed Taiwan for the U.S.

in the context of World War II with a reference to Japan.

Why do you think Beijing has reacted so strongly to what she said?

CHEN MING-CHI: China is overreacting to the whole situation, their aggressive behavior, not only in the Taiwan Strait, in the East China Sea, in the South China Sea.

So China is a party to be blamed.

I think it's -- they are good at twisting reality.

So it's them who provoked.

NICK SCHIFRIN: President Lai Ching-te recently almost trolled Beijing.

He was eating Japanese sushi after China stopped Japanese fish imports.

CHEN MING-CHI: Yes.

NICK SCHIFRIN: Bottom line, though, how important would Japan be if China were to invade or blockade Taiwan?

CHEN MING-CHI: Oh, very important.

I think any country, any democracy's support matter to Taiwan's defense.

See what happened in Ukraine.

We learned a lesson that we have to work together with our line-minded partner for that, never believing the CCP's propaganda.

They just cannot peacefully coexist with democracies.

This is about competition between democracy and authoritarianism.

NICK SCHIFRIN: And in that competition, Taiwan wants a fellow democracy, also seemingly outmatched by its neighbor, to win.

For the "PBS News Hour," I'm Nick Schifrin.