The UK's Brexit referendum has caused a growth in the acceptability of racial, ethnic and religious intolerance, the UN special rapporteur on racism said Friday.

After finishing a two-week fact-finding mission in the UK and Northern Ireland, Tendayi Achiume said in a statement that she found a "growth in volume and acceptability of xenophobic discourses on migration, and on foreign nationals including refugees in social and print media."

Racial and religious-based intolerance was also noticeable in political discourse on both the left and right to the point that it has gained ground in mainstream political parties, she said.

Read more: Is the UK's racist hate crime problem out of control?

Anti-Semitism and Islamophobia

Groups and individuals the UN rapporteur spoke to "raised serious concerns about the failure of political leaders on the left and the right to consistently and unequivocally condemn anti-Semitism and Islamophobia perpetrated in the media, in public spaces and even by members of the UK parliament."

Various branches of the government had shown support for and built the trust of Jewish communities, Achiume said. But similar measures were lacking in the government's outreach approach to Muslims, the entire community of which is sometimes scapegoated "as the presumptive enemy" under vague concepts of extremism.

Deal or no deal? Brexit options boiled down Hard or soft options It's essentially a choice of a harder or softer Brexit. Harder prioritizes border control over trade. UK firms would pay tariffs to do business in the EU, and vice versa. The softest Brexit would see access to the single market, or at least a customs union, maintained. That would require concessions — including the payment of a hefty "divorce bill" — to which the UK has provisionally agreed.

Deal or no deal? Brexit options boiled down A leap into the unknown Businesses have expressed concern about a "cliff edge" scenario, where Britain leaves the EU with no deal. Even if an agreement is reached at the EU bloc level, the worry is that it could be rejected at the last minute. Each of the 27 remaining countries must ratify the arrangements, and any might reject them. That could mean chaos for businesses and individuals.

Deal or no deal? Brexit options boiled down No deal - better than a bad deal? If there is no agreement at all, a fully sovereign UK would be free to strike new trade deals and need not make concessions on the rights of EU citizens living in the UK or pay the financial settlement of outstanding liabilities. However, trade would be crippled. UK citizens in other parts of the EU would be at the mercy of host governments. There would also be a hard EU-UK border in Ireland.

Deal or no deal? Brexit options boiled down Divorce-only deal The EU and the UK could reach a deal on Britain's exiting the bloc without an agreement on future relations. This scenario would still be a very hard Brexit, but would at least demonstrate a degree of mutual understanding. Trade agreements would be conducted, on an interim basis, on World Trade Organization rules.

Deal or no deal? Brexit options boiled down Limited arrangement, like with Canada Most trade tariffs on exported goods are lifted, except for "sensitive" food items like eggs and poultry. However, exporters would have to show their products are genuinely "made in Britain" so the UK does not become a "back door" for global goods to enter the EU. Services could be hit more. The City of London would lose access to the passporting system its lucrative financial business relies on.

Deal or no deal? Brexit options boiled down Bespoke deal: Swiss model Under the Swiss model, the UK would have single market access for goods and services while retaining most aspects of national sovereignty. Switzerland, unlike other members of the European Free Trade Area (EFTA), did not join the European Economic Area (EEA) and was not automatically obliged to adopt freedom of movement. Under a bilateral deal, it agreed to do so but is still dragging its feet.

Deal or no deal? Brexit options boiled down The Norway way As part of the European Economic Area, Norway has accepted freedom of movement – something that no Brexit-supporting UK government would be likely to do. Norway still has to obey many EU rules and is obliged to make a financial contribution to the bloc while having no voting rights. Some see this as the worst of both worlds.

Deal or no deal? Brexit options boiled down A Turkey-style customs union Turkey is the only major country to have a customs union with the EU, as part of a bilateral agreement. Under such an arrangement, the UK would not be allowed to negotiate trade deals outside the EU, instead having the bloc negotiate on its behalf. Many Brexiteers would be unwilling to accept this. It would, however, help minimize disruption at ports and, crucially, at the Irish border. Author: Richard Connor



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Structural racism

Achiume also criticized Prime Minister Theresa May, who as Home Security in 2012, sought to create what she called a "hostile environment" for illegal immigration.

In recent weeks it emerged that Afro-Caribbean British citizens referred to as the "Windrush Generation" from the 1970s and earlier were threatened with deportation when they could not prove their status.

Read more: UK's Theresa May apologizes to Caribbean 'Windrush Generation' for clampdown

May's successor as home secretary, Amber Rudd, resigned over the handling of the fallout on April 29.

Overall, the UN special rapporteur found that the British government has shown leadership and developed legal frameworks to prohibit racial discrimination and intolerance.

However, she said the UK government still had much work ahead to address structural forms of racial discrimination and inequality.

Achiume's findings are preliminary. Her final report will be submitted to the UN Human Rights Council in June 2019.