(VOVworld)- Tens of thousands of protesters from at least 30 cities across the UK took to the streets on Monday to protest against US President Donald Trump's controversial immigration ban.

Some of the banners on display in London (Photo: bbc.com)

At least 25,000 people joined the protests in major streets of London and outside Downing Street, the headquarters of Prime Minister Theresa May. The protesters called on peace lovers to oppose the US top leader’s racial discrimination and xenophobia policy.

Large crowds gathered outside Downing Street (Photo: bbc.com)

The demonstrations took place when Prime Minister Theresa May is paying an official visit to Ireland.

In a vote at the Iraqi parliament on Monday, a majority of parliamentarians supported the promulgation of an order to ban American citizens from entering Iraq in retaliation to the US’ immigration ban on Iraqi citizens.

UN Secretary General Antonio Guterres (AFP File Photo: DENIS BALIBOUSE)

On the same day, addressing the opening of the African Union Summit in Addis Ababa, Ethiopia, UN chief Antonio Guterres criticized the closure of borders "even in the most developed countries in the world".

Last Friday, US President Donald Trump signed an immigration ban on travelers from seven Muslim countries including Syria, Iraq, Iran, Libya, Somalia, Yemen, and Sudan. The decision faced outrage and widespread protests from Muslim countries and even US politicians.