Pro-democracy media mogul Jimmy Lai has said he “never” tried to influence foreign policy or ask foreign officials to take concrete action on Hong Kong, on his first day giving evidence at his national security trial.

Lai has been charged with one count of conspiracy to publish seditious publications and two counts of conspiracy to foreign collusion, under the city’s punitive national security law (NSL), introduced in 2020.

On Wednesday, Lai stridently defended himself against the charges and spoke proudly of the media company he founded and which has been a thorn in the side of Beijing and the Hong Kong government for decades.

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“To participate in delivering freedom was a very good idea for me at that time,” Lai said. “The more information you have, the more you are in the know and the more you are free.”

The 77-year-old has not been heard in public since he pleaded not guilty in January. On Wednesday morning he was led into court by three police officers, and waved at supporters in the public gallery. Swearing an oath on the Bible, Lai sounded hoarse, but his voice grew stronger as he gave testimony. He sat straightbacked at a desk in front of the three-judge panel hearing his case, his reading glasses on the table in front of him.

Prosecutors have alleged Lai asked the US and other countries to impose sanctions or “engage in other hostile activities” against China and Hong Kong, in response to the crackdown on the pro-democracy movement in the wake of the 2019 protests.

Lai was asked about dozens of foreign individuals listed on a prosecution document of his “external political connections”. It included the then US president Donald Trump and senior members of his administration, Taiwan’s former president Tsai Ing-wen, and a number of UK, US and Taiwan activists, academics, politicians and journalists.

Lai confirmed meeting some, but he denied asking for any concrete action beyond speaking in support of Hong Kong.

“Did you try to influence foreign policy on China through these people?” his lawyer asked.

“Never,” replied Lai.

“Did you ever request these people to take any action against China or Hong Kong?”

“Never,” Lai replied again.

Lai told the court he had never met, spoken to, or exchanged messages with Trump, but believed the then-president had been briefed about him. He confirmed that in July 2019, shortly after the start of the mass pro-democracy protests, he met the then vice-president Mike Pence, secretary of state Mike Pompeo, and the speaker of the House Nancy Pelosi in Washington DC. He said he did not request anything of Pence and Pompeo, and did not speak at the Pelosi meeting.

“I would not dare to ask the vice-president to do anything, I just relayed to him what happened in Hong Kong when he asked me,” Lai said. “I asked him to voice up for Hong Kong and support us, but there was never anything particularly that I asked for.”

Lai also revealed he knew Tsai Ing-wen before she became president of Taiwan, considered her a friend, and met her several times after. “I think her interest in meeting me is of course because of my media … She’d ask me sometimes about the general opinion of the people … I think it was more PR for her than anything she wanted to discuss with me of substance.”

He also introduced her to US defence officials because her aide told him she wanted to know what the Trump administration was thinking internally about Taiwan.

Asked why he wanted to help Taiwan, Lai said: “Taiwan is the only democracy of Chinese people, for the whole history of Chinese people.”

Lai denied testimony from an earlier witness that he appeared to become more politically radicalised after a 2019 foreign policy speech by Pence which markedly extended the US government’s hawkishness on China.

“If I was radical, I was radical all along,” he said.

The case against Lai centres on various media appearances and social media posts and more than 160 articles published in the now-closed tabloid Apple Daily, which supported the 2019 pro-democracy protests and often criticised Beijing’s leadership.

Lai told the court he became political after the Tiananmen Square massacre on June 4 1989, and decided to use the wealth from his clothing business to start a media company, and later launched Apple Daily.

He said there was no editorial policy regarding political stances and that Apple Daily became popular because it shared the core values of Hong Kong people. “We assume anybody given the freedom to express would express the core values of Hong Kong values. Rule of law, freedom, pursuit of democracy, freedom of speech, freedom of religion, freedom of assembly.”

Lai said he regarded advocating for the independence of Hong Kong as “a reality too crazy to think about” and banned discussion of it by his paper and staff.

Lai is expected to spend weeks giving testimony. His case is one of the most prominent under the NSL, with western countries and rights groups demanding his release. But Hong Kong and Beijing have rejected the criticism, condemning Lai as “a voluntary political tool of foreign forces trying to curb China through Hong Kong”.

The crowd outside the court on Wednesday morning was smaller than for Tuesday’s sentencing of the 45 pro-democracy figures. About 100 people were queued up by 8am, huddled against the driving rain and wind as a heavy police presence patrolled the area.

William Wong, 64, said he had long followed the case against Lai and Apple Daily, which was forced to close in 2021 after police raids and the arrests of Lai and senior editors.

“I’m a reader of Apple Daily. It’s been a few years, and Mr Lai is jailed. He’s elderly and his health is not too well, so I want to support him in person.”

At the front of the queue a buoyant group of Lai supporters rallied themselves together, sharing takeaway hot chocolates and warming themselves under space blankets.

“We really want to support him. It’s for us Hongkongers, for Hong Kong, for my Hong Kong,” said CY Chen, a man in his 70s who said he had been jailed on charges of illegal assembly during the 2019 protests.

“People like Jimmy Lai are very few nowadays, people who can speak for us. So we treasure him and we care about him.”

Lai is being held in solitary confinement at Hong Kong’s Stanley prison, serving a separate jail term, and concerns have been raised for his health.

“The case of Jimmy Lai is not an outlier, it’s a symptom of Hong Kong’s democratic decline,” the Committee to Protect Journalists said in a statement on Monday.

“Hong Kong’s treatment of Jimmy Lai – and more broadly of independent media and journalists – shows that this administration is no longer interested in even a semblance of democratic norms.”

Last month, British prime minister Keir Starmer told parliament that Lai, who has British citizenship, was “a priority” for his government. On Monday Starmer raised the issue in a meeting with the Chinese leader, Xi Jinping.