What you need to know:
- Moments before her arrival, Chinese state media announced advanced Su-35 fighter jets were crossing the Taiwan Strait. The brief report had no details on timing or precise location of the crossing.
United States House Speaker Nancy Pelosi landed in Taiwan on Tuesday evening, defying a string of increasingly stark warnings and threats from China that have sent tensions between the world's two superpowers soaring.
Pelosi, second in line to the presidency, is the highest-profile elected US official to visit Taiwan in 25 years and Beijing has made clear that it regards her presence as a major provocation, setting the region on edge.
Live television images showed the 82-year-old lawmaker, who flew on a US military aircraft into Taipei Songshan Airport, being greeted on arrival by foreign minister Joseph Wu.
Pelosi is currently on a tour of Asia and while neither she nor her office confirmed the Taipei visit, multiple US and Taiwanese media outlets reported it was on the cards -- triggering days of anger from Beijing.
Moments before her arrival, Chinese state media announced advanced Su-35 fighter jets were crossing the Taiwan Strait. The brief report had no details on timing or precise location of the crossing.
"The US breach of faith on the Taiwan issue is despicable," Chinese foreign minister Wang Yi said in comments published on his ministry's website earlier Tuesday that did not specifically mention Pelosi.
No need for 'crisis'
China considers self-ruled, democratic Taiwan as its territory and has vowed to one day seize the island, by force if necessary.
It tries to keep Taiwan isolated on the world stage and opposes countries having official exchanges with Taipei.
In a call with US President Joe Biden last week, Chinese President Xi Jinping warned the United States against "playing with fire" on Taiwan.
While the Biden administration is understood to be opposed to a Taiwan stop, White House National Security Council spokesman John Kirby said Pelosi was entitled to go where she pleased.
"There is no reason for Beijing to turn a potential visit consistent with longstanding US policies into some sort of crisis," he told reporters.
The last House Speaker to visit Taiwan was Newt Gingrich in 1997.
Kirby cited intelligence that China was preparing possible military provocations. He said that while Washington did not fear a direct attack on Pelosi's plane, it "raises the stakes of a miscalculation".
Kirby reiterated, however, that US policy was unchanged toward Taiwan.
This means support for its self-ruling government, while diplomatically recognising Beijing over Taipei and opposing a formal independence declaration by Taiwan or a forceful takeover by China.
Meanwhile, Moscow said it was "absolutely in solidarity with China", calling the prospect of a Pelosi visit "pure provocation".
China has refused to condemn Russia's invasion of Ukraine and has been accused of providing diplomatic cover for the Kremlin by blasting Western sanctions and arms sales to Kyiv.
All eyes on Taiwan
Pelosi left Kuala Lumpur Tuesday after meeting Malaysian Prime Minister Ismail Sabri and Foreign Minister Saifuddin Abdullah.
So many people were tracking the US military plane ferrying her on FlightRadar that the website said some users experienced outages.
The plane took a circuitous route that studiously avoided the South China Sea -- which Beijing claims -- before heading up the east coast of the Philippines.
Press access around Pelosi has been tightly restricted so far and limited to a handful or short statements confirming meetings with officials.
Her itinerary includes stops in South Korea and Japan -- but the prospect of a Taiwan trip had dominated attention.
Taipei's government remained silent on whether she would visit even as local media published reports showing her presence was all but guaranteed.
The capital's famous Taipei 101 skyscraper was illuminated with the words "Speaker Pelosi... Thank You" on Tuesday night before her plane had arrived.
- 'Seek to punish Taiwan' -
Taiwan's 23 million people have long lived with the possibility of an invasion, but that threat has intensified under Xi, China's most assertive ruler in a generation.
The island's military on Tuesday said it was "determined" to defend it against increased threats by China over the potential Pelosi visit.
"The probability of war or a serious incident is low," tweeted Bonnie Glaser, director of the Asia programme at the US-based German Marshall Fund think tank.
"But the probability that... (China) will take a series of military, economic, and diplomatic actions to show strength & resolve is not insignificant," she added.
"Likely it will seek to punish Taiwan in myriad ways."
Taipei's Council of Agriculture on Tuesday said China had suspended the import of some Taiwanese goods, including some fishery products, tea, and honey. The council said China cited regulatory breaches.
Pelosi's potential visit has been proceeded by a flurry of military activity across the region that highlights how combustible the issue of Taiwan is.
Last week both Taiwan and China held live fire drills