Speaking in Washington DC, Ms Braverman outlined how she believed the current system was "outdated".

She branded the number of displaced people in the world as an "epoch-defining challenge" - the same language the government uses to describe China.

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Uncontrolled and illegal migration is an "existential challenge for the political and cultural institutions of the West", she said, adding that "uncontrolled immigration, inadequate integration, and a misguided dogma of multiculturalism have proven a toxic combination for Europe over the last few decades".

The speech was panned by NGOs, campaigners and politicians, with Amnesty International saying it was "a display of cynicism and xenophobia".

Part of her speech criticised how current levels of migration have led to "undermining the stability and threatening the security of society" in "extreme cases".

She said: "We are living with the consequence of that failure today. You can see it play out on the streets of cities all over Europe. From Malmo, to Paris, Brussels, to Leicester."

"If people are not able to settle in our countries, and start to think of themselves as British, American, French, or German, then something is going badly wrong," she added.

Ms Braverman said "we now live in a completely different time" to 1951 when the UN Human Rights Convention was signed.

She went on: "Is the Refugee Convention in need of reform?

"What would a revised global asylum framework look like?

"How can we better balance national rights and human rights, so that the latter do not undermine national sovereignty?"

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Ms Braverman also questioned whether courts have redefined asylum to be granted for people suffering "discrimination" instead of "persecution" - especially in the context of someone who is gay or a woman.

"Where individuals are being persecuted, it is right that we offer sanctuary?

"But we will not be able to sustain an asylum system if in effect, simply being gay, or a woman, and fearful of discrimination in your country of origin, is sufficient to qualify for protection."

'The need is not for reform'

The UN's refugee agency, the UNHCR, responded to Ms Braverman's speech by saying the convention "remains as relevant today as when it was adopted in providing an indispensable framework for addressing those challenges, based on international co-operation".

"The need is not for reform, or more restrictive interpretation, but for stronger and more consistent application of the convention and its underlying principle of responsibility-sharing," it added.

"An appropriate response to the increase in arrivals and to the UK's current asylum backlog would include strengthening and expediting decision-making procedures.

"This would accelerate the integration of those found to be refugees and facilitate the swift return of those who have no legal basis to stay.

"UNHCR has presented the UK Government with concrete and actionable proposals in this regard and continues to support constructive, ongoing efforts to clear the current asylum backlog."

The speech and its contents were met with criticism from a range of charities, MPs and campaigners.

Ben Bradshaw, a gay Labour MP and former cabinet minister, asked if any "LGBT or any other Tories" were prepared to condemn the home secretary, adding that "being gay is enough to result in persecution or death in many countries".

Michael Fabricant, a Tory MP and a patron of the Conservative LGBT+ group, said that "if someone simply claims to be gay in order to seek asylum, that should not lift the bar to entry to the UK".

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He added: "However, if someone has experienced persecution from the country from which they are escaping, it presents a different and far more persuasive case. Each application should be considered carefully on its merits."

Fellow Conservative MP David Davis said "it is perfectly reasonable to ask why there are so many migrants", but looking at the origin of where people come from - and influencing factors like Western foreign policy and wars in such regions, should also be taken into account.

Braverman 'spot on'

Ms Braverman's junior in the Home Office, Robert Jenrick, supported her speech - saying the authors of the international laws criticised by the secretary of state would be "appalled" with how the system is now mired in organised criminality and exploited by economic migrants.

Tory MP Scott Benton said Ms Braverman was "absolutely spot on", adding that "she's right to highlight the need for reform and the British public are with her on this issue and so many others".

Lord Dubs, the Labour peer, who arrived in the UK as a child refugee from the Nazis in Czechoslovakia, said that Ms Braverman's comments were "shocking".

"In many countries being gay is an imprisonable offence. For some, it means the death penalty," he said.

"She's repeating the shameful policy that people should not be treated as refugees if they arrive here by boat.

"But she's closed virtually all other means of arrival."

'Cynicism and xenophobia'

Sacha Deshmukh, Amnesty International UK's chief executive, said: "The Refugee Convention is a cornerstone of the international legal system and we need to call out this assault on the convention for what it is - a display of cynicism and xenophobia.

"The Refugee Convention is just as relevant today as it was when it was created, and verbal assaults from the home secretary don't alter the harsh realities that cause people from countries such as Sudan, Afghanistan and Iran to flee from conflict and persecution."

He added: "Instead of making inflammatory speeches decrying the rights of people fleeing persecution and tyranny, Suella Braverman should focus on creating a functioning UK asylum system that tackles the massive backlog her policies have created, so as to be able to meet the limited refugee responsibilities that fall to the UK."

Josie Naughton, chief executive of Choose Love, said: "It is the Home Secretary, not the global refugee convention, that is out of touch with the modern age.

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"In a world marred by conflicts and displacement, more and more people are fleeing war zones and persecution in search of safety.

"On top of natural disasters, and rising climate concern, we all know that the number of people being displaced will only increase globally.

"The UN's 1951 Refugee Convention was put in place to protect every human being searching for safety, fleeing war zones, danger and threats to their life and freedoms. More than ever, the world must come together and unite behind it. We cannot solve this problem by seeking to undermine fundamental human rights. Working together is the only solution."