A 20-foot anti-President Donald Trump balloon is set to fly over Parliament Square Gardens in London next Friday during the president's visit to the UK, his first one there since winning the election in 2016.

The balloon mocks Trump, portraying him as a giant baby. Sky News reports it must be tethered to the ground and fly no higher than 98 feet.

Its flight coincides with a "Stop Trump" march in central London.

News sources say the group behind the balloon describes itself as anti-fascist "art activists."

"We didn't get off to the best start with the Mayor's office over this, who originally told us that they didn't recognize Trump Baby as legitimate protest," activist Leo Murray told Sky News.

"But following a huge groundswell of public support for our plan, it looks like City Hall has rediscovered its sense of humor. Trump Baby will fly!" he continued.

The website, Unilad, reports a petition in favor of the balloon received more than 10,000 signatures. The group behind the balloon has a Crowdfunder site, which shows they've raised more than $30,000.

"But he (Trump) really seems to hate it when people make fun of him," the Crowdfunder site states. "So when Trump visits the UK on Friday the 13th of July this year, we want to make sure he knows that all of Britain is looking down on him and laughing at him."

Fox News reports reaction to the balloon has been mixed. Some find it funny, but others are not smiling.

Brexit leader and former UK Independence Party leader Nigel Farage did not mince words, tweeting, "Sadiq Khan has allowed an inflatable 'Trump baby' blimp to fly in London. This is the biggest insult to a sitting US President ever."

Sadiq Khan has allowed an inflatable “Trump baby” blimp to fly in London. This is the biggest insult to a sitting US President ever. https://t.co/4IRVlG7Gz6 — Nigel Farage (@Nigel_Farage) July 5, 2018

Khan is the mayor of London. Trump and he have often taken verbal jabs at each other.

"The Mayor supports the right to peaceful protest and understands that this can take many different forms," a spokesperson for Khan said, according to Sky News.

"Let me ask you, does any of you seriously think that if an application to fly an Obama blimp, of Obama as a young, crying baby above Parliament Square when he came here during the referendum to tell us to vote remain, do you actually think that would have been allowed?" asked Farage on his "Leading Britain's Conversation" radio show.

"You can't stop people from protesting, expressing their opinion, but I do think there's a never ending war of words, and it does cut both ways because the President invites a fair bit of it," Farage continued.

"But this never ending war of words between Sadiq Khan and Donald Trump is frankly ridiculous," he said.

The "art activists" also mock Khan on Twitter over the granting of approval to the group, tweeting, "HUGE news coming in: DONALD J TRUMP BABY WILL FLY! @SadiqKhan tried to play hard ball - in the end he had to make a Deal. No surprise - he's never won anything in his life! Sad - but True! London here I come!"

HUGE news coming in: DONALD J TRUMP BABY WILL FLY! @SadiqKhan tried to play hard ball - in the end he had to make a Deal. No surprise - he's never won anything in his life! Sad - but True! London here I come! https://t.co/j3KCPimHI2 pic.twitter.com/oc2VKWKSN1 — Trump Baby (@TrumpBabyUK) July 5, 2018

The 'Trump baby' balloon might not be the only huge inflatable floating over London. Fox News reports a crowdfund campaign has been launched for a counter-protest.

According to Fox News, Yanny Bruere, a man from the UK who now lives in Spain, wants to raise funds for a "baby Khan" balloon that would be the same size as the 'Trump baby' inflatable.

Fox News reports this campaign has raised so far nearly $24,000.

The "pro-Brexit, pro-Trump" group, Westmonster, tweeted, "OUCH: Campaign for 'Baby Khan' balloon smashes £10k target as public express anger at London's Mayor."

OUCH: Campaign for ‘Baby Khan’ balloon smashes £10k target as public express anger at London’s Mayor. ‘Let’s see if free speech applies to all and whether or not Mr. Khan and the London Assembly will also approve this.’https://t.co/AAdZe4o3lv — Westmonster (@WestmonsterUK) July 6, 2018

A "Giant Sadiq Khan 'baby balloon to fly over London" Crowdfunder site states, "In light of the Donald Trump 'Baby Trump' ballon (sic) being allowed to fly over London during his visit to the U.K., let's get a 'baby Khan' one and see if FREE SPEECH applies to all and whether or not Mr Khan and the London assembly will also approve this."

US ambassador to Great Britain Woody Johnson told reporters on a conference call that he thinks Trump is "aware" of the planned protests in London, including the giant balloon, according to DailyMail.com.

"But you know, the president is keenly focused on what his objectives are," Johnson said. "He appreciates free speech, both in this country and in our country."

"It's one of the things that binds us together, the freedoms that we share," he continued.