"No mega-embassy, no mega-embassy", the crowd chanted over and over on Saturday's protest against China's super-embassy plan. The feeling of anger and concern among protesters  — estimated to be in the thousands — was strong.

Saturday's demonstration was billed by its organisers as the "last chance" to put pressure on Labour to not approve China's application to turn the former Royal Mint in central London into an embassy. And they certainly made their point of view crystal clear. Protesters who took to the stage were powerful in their words and animated in their delivery.

They also assembled something of an all-star cast to heap pressure on the Government as cross-party MPs, including Tory Sir Iain Duncan Smith, Reform UK's Danny Kruger and Lib Dem Bobby Dean, joined forces to call for the plans not to go ahead as expected.

Conservative leader Kemi Badenoch made an appearance and received warm applause as she took to the stage, where she didn't pull any punches, claiming the Government "seems to be scared of China".

“I am standing here with you today because I believe in freedom," she said in an empathetic tone as she addressed the crowd.

“I’m standing with you today, because I know what it is like to live without freedom.

“We take it for granted in the United Kingdom because we have had it for so long, but those who have lived under oppressive regimes, those who have lived under authoritarianism, those who have lived under communism, know what that suffering is like, and we do not want to see that here."

This was the first time I had attended one of the protests against the so-called super embassy, which Sir Keir Starmer appears set to approve next week.

It was hard to hear how incredibly concerned so many of the protesters were, and it seemed apparent that many were not confident in the PM.

One demonstrator I spoke to was Tenzin Sangmo, an NHS nurse who made the journey to the capital from Bristol.

She's originally from Tibet and was proudly wearing the Tibet flag as we chatted while the crowd numbers swelled.

“I'm very concerned that this Chinese mega Embassy is going to be like a spy hub, where they will monitor every movement of our diaspora communities," said Tenzin, who later addressed the crowds on the stage.

“So, being in Britain, a free world, a country that respects democracy, I feel giving this historical space to the Chinese mega embassy is going to be very worrying, and it is a threat to national security.

“That's why I feel that it's very important for me to come here and have my right to protest and to tell the Government that they need to rethink this proposal, and especially to Steve Reed [Communities Secretary]. I want to tell him that you need to think very carefully before signing this proposal.”

Jonathan Chang, in his 40s, is from Hong Kong and moved to the UK in the past few years. He said he left his homeland because the political situation was "getting worse and freedom was infringed".

When asked how concerned he is by the embassy proposals, he said: "The simple answer, I think it's very terrible.

"You see the plans [for the embassy] on the news; they have many underground chambers.

"I think they cannot explain what the purpose of those chambers is, maybe to detain something, someone they don't like or arrest someone against their regimes."

He added: "I'm not quite optimistic because the current Prime Minister is buying to China's benefit."

There was a feeling among those at the protest that Sir Keir is willing to approve the embassy application because of an economic deal or agreement between the UK and China.

Sir Keir is set to travel to Beijing in the near future, as he looks to secure stronger ties.

Another protester, Clara, put together some of the hundreds of placards she helped bring down from the north of England.

Clara, who is also originally from Hong Kong and is in her 40s, said she is worried the UK is "selling out" its own national security.

"One important message is that we are worried the UK will fall for the so-called economic benefits from China, but what we do see is a lie," Clara explained.

She added: "We are saying that Starmer is putting the national security of the UK at risk, because he's imagining he can get some trade benefits from China. We don't think that's decided."

One protester drew attention as he wore all black, and a helmet and goggles, which you may expect to be donned by riot police.

His friend told me the clothing was inspired by what protesters in Hong Kong wore in 2019.

The protester, who did not want to be identified, told me: "I ran away from Hong Kong because of China. I don't want the same thing happening in the UK."

When I asked if he was worried about this, he simply nodded his head.

The next few days will likely be a nervous wait for these protesters, although it's widely expected the controversial embassy will get the green light.

Ministers say they will make a decision on whether to approve China’s planning application for the embassy by Tuesday.