WATCH: Colossal anti-Trump protest attracts tens of thousands to London during presidential visit

"I think they like me there." - Donald Trump ahead of his visit to the UK.

Tens of thousands of demonstrators have taken to the streets of London to protest Donald Trump's four-day "working visit" to Britain on the day he is scheduled to meet both Theresa May and the Queen. On his only full day of business during his trip to Britain, protests began in Parliament Square this morning where the Trump baby blimp was flying high, or at least high-ish, depicting the US President as a screaming, fluorescent orange baby holding a mobile phone with the Twitter app open. The president's visit has seen the largest police operation since the 2011 riots with a £10 million "ring of steel" erected to keep protesters away from Trump. https://twitter.com/PoliticsJOE_UK/status/1017681553885974528 https://twitter.com/Mikel_Jollett/status/1017792265912135680 Protesters converged to march against the president and his right-wing policies, ranging from immigration and race-relations to gender equality and climate change, with many travelling via coach from cities up and down the country. Sheila, one of the artists behind the Trump baby inflatable, told JOE.co.uk: "Whilst representing Trump's inflated ego, and his thin skin, this is also about opposing his hate-fuelled, misogynistic politics." https://twitter.com/PoliticsJOE_UK/status/1017690565603942400 Madelaina, who came dressed as 'the EU supergirl', simply said: "I hate Donald Trump and I hate Brexit." https://twitter.com/JohnWilson14/status/1017768951768592384 An unnamed woman, dressed as a Guantanamo Bay detainee with an upside down the American flag and her head covered, said: "The flag's upside down not to be offensive but to protest the locations of US military bases in the UK. We're at RAF Menwith Hill in North Yorkshire every week." https://twitter.com/PoliticsJOE_UK/status/1017721810320838656 Ron, a 47-year-old American business consultant told us: "I found it quite insulting the American Embassy advised us to keep a low profile. There's only one American who shouldn't be here today." Erin, a teacher who arrived at the protests dressed as a pigeon, said: "I have an Instagram account called the pigeon. I'm from California on holiday here. My friends told me and I HAD to come see baby Trump." https://twitter.com/PoliticsJOE_UK/status/1017697343586684928 Following the morning gathering underneath the Trump baby blimp at Parliament Square, many made their way to Portland Place where a rally organised by the Stop Trump collation began around 2pm, culminating in speeches being delivered by Owen Jones and others at Trafalgar Square. https://twitter.com/PoliticsJOE_UK/status/1017747227979239430 A petition to prevent an official state visit by Trump began in 2017 and attracted 1.8 million signatures. The issue was then debated in parliament several times along with the President himself delaying his visit on more than one occasion. This is now, apparently, a 'lower-level' working visit. https://twitter.com/PoliticsJOE_UK/status/1017747376373731328 Donald Trump will meet the Queen at Windsor Castle late on Friday afternoon for high tea.