TAIPEI (BLOOMBERG) – The path of House Speaker Nancy Pelosi’s US military plane en route to Taiwan was notable for how carefully it avoided the South China Sea.

The closely watched trip was one of the most controversial official US visits in recent memory, and the flight path underscored a remarkable degree of caution as Washington tries to avoid further angering Beijing and triggering unintended consequences.

Flight-tracking data shows that the aircraft carrying Mrs Pelosi, which landed in Taipei shortly before 11pm local time, completely avoided flying through the skies above the contested South China Sea.

Instead of flying northeast out of Kuala Lumpur directly over the South China Sea – a journey that might have brought her plane close to Chinese military facilities built on reclaimed land on islets and reefs including in the Spratly Islands – Mrs Pelosi’s plane flew southeast straight across the Indonesia part of Kalimantan, or Borneo, before turning north and flying to the east of the Philippines, according to imagery provided by Flightradar24.

“I imagine the flight path will take extra caution into considerations,” said Ms Meia Nouwens, a senior fellow for Chinese defence policy and military modernisation at the International Institute for Strategic Studies in London.

“Of concern may have been the militarisation of the three largest Chinese man-made islands in the Spratlys, which are equipped with permanent defence facilities and weaponry.”

Mrs Pelosi’s visit to the democratically ruled island, which is claimed by China, has resulted in heightened tensions between Washington and Beijing.

As Mrs Pelosi arrived in Taiwan, China announced it would stage a series of military drills including “long-range live firing in the Taiwan Strait” from Tuesday evening.

It reflected China’s strong condemnation of the visit by the highest-ranking US elected official to come to the island in 25 years.