Back to William Lai's speech.

He has thanked former President Tsai Ing-wen and her team for the past eight years of their service to Taiwan.

"You have all helped build a solid base for Taiwan's development," he said, urging the crowd to a round of applause.

"I also want to thank my fellow citizens... for refusing to be swayed by external forces, for resoluting defending democracy... and for turning a new page in Taiwan's history."

Seperately, we have just had this photo from Taiwan's Ministry of Defence, where William Lai's portrait has replaced that of former president Tsai Ing-wen, bringing to an end her eight years in power.

Image source, Ministry of Defence

Lai opened his speech saying he will accept the responsibility of leading Taiwan with an "unwavering heart".

"When I was young, I was determined to practice medicine and save lives. When I went into politics, I was determined to transform Taiwan.

"Now, standing here, I am determined to strengthen Taiwan," he said.

Image source, Taiwan Presidential Office

William Lai has begun speaking.

This is his first presidential address to the thousands of guests and foreign delegates who were invited to the inauguration, and the Taiwanese across the island and abroad who will tune in to listen to their new president.

It looks like we are moments away from Lai's inaugural speech as Taiwan's 16th president. Lai and Hsiao have arrived at the plaza outside the Presidential Office and the military is conducting a 21-gun salute.

Image source, Taiwan Presidential Office

Image source, Taiwan Presidential Office

The Chinese government is yet to issue a statement on Monday, but they made their position on Taiwan clear over the weekend.

On Sunday, state media Global Times published an article caling for peace. It said many people in Taiwan have urged Lai not to further provoke Beijing, and called him a "secessionist".

On Friday, the Chinese embassy in the UK held a press briefing, where Minister and First Staff Member Yang Xiaoguang asked the UK government to not endorse the ceremony.

He also urged the UK to not send a delegation, or allow relevant personnel from Taiwan to visit the UK or have any official contact with Taiwan.

Earlier last week, a spokesperson for China's Taiwan Affairs Office warned that Taiwan's new leader "must seriously" consider the question of whether Taiwan wants peaceful development or confrontation.

Image source, Embassy of People's Republic of China in the UK

Over the weekend, Taiwan's defence ministry reported at least 13 Chinese military aircraft and 14 Chinese naval vessels in waters and airspace “around Taiwan”. Here's a video showing at least two military choppers flying across the strait in the Chinese costal city Pingtan, the closest point in China to Taiwan's main island.

Taipei authorities have said they were anticipating intensified military activity from Beijing leading to Lai's inauguration. Last week, Reuters news agency reported that China's military has "sailed and flown closer to Taiwan in recent weeks than it has before", and had staged mock attacks on foreign vessels.

The island's deputy defence minister Po Horng-huei had said Taiwan's military is ready for any moves "by the other side" that may damage regional peace and stability.

China sees self-ruled Taiwan as a breakaway province that will eventually be under Beijing's control and has not ruled out the use of force to take the island. But Taiwan sees itself as distinct from the Chinese mainland, with its own constitution and democratically-elected leaders.

Rupert Wingfield-Hayes
in Taipei

The celebrations continue before Lai gives what will be his first presidential address.

One of the highlights so far has been a large, blue, rather trippy horse - which entered the venue almost like a Trojan horse and blew smoke from its nostrils.

Image source, Taiwan State Media

It has no particular cultural significance. It's called the rain horse or "yuma" - it's from a popular theatre group that mosty does shows for children, hence the furry animals, the birds and all the dancing.

All of this colour and performance is a very deliberate celebration of Taiwan's diverse culture. There was a group, for instance, that was rapping in four languages - Mandarin, Hakka, Taiwanese and English.

Everything about this is saying: look at us, we are free, we are multi-cultural. This is Taiwan. Of course,. the sub text is "we are not China".

That is the message they are sending over and over again, even it, at times, it feels slightly heavy-handed.

An unofficial delegation from the US, and representatives from Japan, Australia and South Korea are among the foreign dignitaries attending the inauguration ceremony.

Also present are representatives from Paraguay, Eswatini, Palau and St Lucia - which are among a handful of countries that maintain formal diplomatic ties with Taiwan.

In January this year, the tiny Micronesian island of Nauru cut ties with the island in favour of Beijing, leaving Taiwan with just 12 diplomatic allies.

Just over an hour ago, William Lai took the oath of office at the presidential palace in Taipei. Watch the moment he was officially sworn in, at a ceremony attended by dozens of foreign delegations.

Image source, Getty Images

Lai's vice-president, Hsiao Bi-khim, appears to infuriate Beijing just as much as Lai, if not more.

The 52-year-old was born in Japan and mostly grew up in the US, cementing her links to Taiwan's strongest allies, which are also China's toughest diplomatic relationships.

China has called Ms Hsiao a "diehard Taiwan independence separatist".

Beijing has twice sanctioned the high-profile diplomat from entering mainland China and has also prohibited investors and firms related to her from working with organisations on the mainland.

US Secretary of State Antony Blinken has congratulated William Lai on his inauguration, adding the US looks forward to working with him "and across Taiwan's political spectrum to advance our shared interests and values".

Former US officials are part of an unofficial American delegation at the swearing-in ceremony today.

Although the US does not recognise Taiwan officially, it remains its biggerst and most important ally.

Just as Lai was being sworn in, China's Commerce Ministry said, external on Monday that it will sanction several US companies “involved in arms sales to Taiwan".

These include Boeing Defense Space & Security, which builds military aircaft, and General Atomics Aeronautical Systems and General Dynamics Land Systems - both of which manufacture military vehicles such as tanks and unmaned aerial vehicles.

The companies have been added to Beijing's List of Unreliable Entities, and are prohibited from engaging in import and export activities related to China, the ministry said.

Chinese social media has been relatively quiet on Lai's big day. There is no hashtag being created on this, and other Taiwan-related hashtags haven't gained much traction today, though it is unclear if it is because it isnt generating conversation or whether there might be a certain degree of censorship happening.

Those who did talk about Lai and his inauguration ceremony are speculating on the contents of his speech, saying they are waiting to see if it will send a clear message to Beijing.

They also point out that they expect Lai to follow Tsai's pathway of being close to the US and distant from the mainland.

Others are calling for China to use force to reclaim Taiwan - something Beijing has long threatened - others say that Beijing can talk the talk, but not walk the walk.

China sees self-ruled Taiwan as a breakaway province that will eventually be under Beijing's control, but Taiwan sees itself as distinct from the Chinese mainland, with its own constitution and democratically-elected leaders.

Rupert Wingfield-Hayes
in Taipei

Going back to the moment the inauguration ceremony happened. As the leader of Taiwan's legislature Han Kuo-yu handed the seals of office to President William Lai and his vice-president, Hsiao Bi-khim, there were murmurs in the crowd.

They know very well that Lai and Han are political enemies. Han Kuo-yu, from the oppositon KMT, had run for president in 2020 and lost.

There is no love between these two men at all and that is why the bitter fighting has begun in the legislature in the last few days.

Image source, Taiwan presidential office

These are some of the first images of Taiwan's former president Tsai Ing-wen, new president William Lai and the new vice-president Hsiao Bi-khim, outside the Presidential office building in Taipei,

Image source, Reuters

Image source, Taiwan Presidential Office

In his first duties as president, Lai is signing appointment decrees for his Premier-designate Cho Jung-tai, Secretary-General to the president Pan Men-an and National Security Council Secretary-General Wellington Koo.

They will be sworn in shortly.

Outside, Taiwan's military band continues playing songs that speak of Taiwan's indigenous and cultural history.

Rupert Wingfield-Hayes
in Taipei

I just met new Taiwanese citizens - people who have come from Indonesia and Vietnam and have become naturalised here.

They voted for the first time in a Taiwan election in January. They were extremely excited - they talked about how amazing it is to be voting in Taiwan and to be accepted as new citizens here, so they are real poster children for former president Tsai Ing-wen's policy of accepting new people into Taiwanese society.

They spoke fluent Mandarin and said: "We need to protect Taiwan because Taiwan is home now".

Image source, Taiwan presidential office

The swearing-in ceremony for William Lai and Hsiao Bi-khim has concluded and a military parade is now happening at the plaza outside the Presidential Office in Taipei.

A photo montage showing outgoing president Tsai Ing-wen and Lai side by side is playing in a big screen at the plaza as Tsai, Lai and Hsiao wave to the crowd.

"Being able to lead... is the biggest pride of my life," Tsai was quoted saying in the video. Tsai has served as Taiwan's leader for eight years.

"We have to believe in ourselves, we have to believe in Taiwan and continue walking down the right path," Lai was quoted saying.

Hsiao Bi-khim has also taken her oath of office and been sworn in as Taiwan's vice-president.

China had previously called Ms Hsiao a "diehard Taiwan independence separatist". Beijing has twice sanctioned the high-profile diplomat from entering mainland China and has also prohibited investors and firms related to her from working with organisations on the mainland.

Image source, Taiwan Presidential Office