London(CNN) The news that Joe Biden and Kamala Harris are set to be the next President and Vice President of the United States has sparked much speculation as to what this means for the United Kingdom -- a country that likes to think of itself as America's closest ally.
"This country's had a good relationship with the White House over the last few years," UK Prime Minister Boris Johnson said at a Downing Street press conference on Monday. "It's had a good relationship with the White House for many, many years and I have no doubt that we will continue to have a very, very strong, very close relationship with our American friends."
But when Johnson tweeted congratulations to Biden and Harris over the weekend, his message was dismissed as insincere by critics in the UK, who pointed out that members of Johnson's government and Conservative lawmakers had openly endorsed the re-election of Donald Trump.
The most damaging indictment, however, came from a former Barack Obama spokesperson, Tommy Vietor, who tweeted: "This shapeshifting creep weighs in. We will never forget your racist comments about Obama and slavish devotion to Trump."
A Biden aide told CNN that "President-elect Biden believes deeply in the special relationship, and he looks forward to making that partnership even stronger. To be sure, our British allies are indispensable partners across the range of challenges, and that view is uniformly held among those close to the President-elect."
However, the perception that Johnson is a Trump-style leader -- whether it is fair or not -- has traveled across the Atlantic. Indeed, Biden himself was reported to have described Johnson as a "physical and emotional clone" of Trump last December.
American and British government officials told CNN that, while they believe the two leaders will have a functional working relationship, there might be barriers because of personality differences.
The "racist comments about Obama" that Vietor refers to came about during the 2016 Brexit referendum. Obama had reluctantly intervened in the Brexit debate, saying he would prefer the UK to stay in the European Union. In response, Johnson -- not the prime minister at the time, but a Conservative lawmaker and one of the leading figures in the Brexit campaign -- wrote that "the part-Kenyan President" had an "ancestral dislike of the British empire."
Tyson Barker, a former State Department official under President Obama and Vice President Biden, told CNN "there is a distaste for Boris Johnson's populism and his willingness to lie. That might irk people at lower levels of a Biden administration." However, he added that Biden's "political instinct is to be a healer and I cannot see how that would not extend to the UK."
The UK government is very aware that this perception of Johnson as "Trumpian" exists in some corners of Washington, and there appears to be a real effort to get ahead of any uncomfortable first introductions.
"There's a whole bunch of areas where our priorities do align," said a senior figure in Johnson's government, adding that "there is a bit of relief on our side that we are going to be dealing with someone more consistent and reliable."
A spokesperson for Johnson was equally upbeat when briefing journalists on Monday, saying that "the Prime Minister is looking forward to working with the President-elect in the weeks and months ahead" -- a comment that risks drawing the ire of Trump, who is yet to accept the result of the election and considers Johnson a "friend."
Even if Biden and Harris are able to move beyond any preconceived ideas regarding Johnson personally, Biden has publicly criticized a central pillar of the Prime Minister's Brexit strategy.
Earlier this year, Johnson introduced a bill that, though very technical, could force the need for a border between Ireland, an EU member state, and Northern Ireland, which leaves the Brexit transition period, along with the rest of the UK, at the end of this year if no trade deal is agreed.
A British cabinet minister has admitted that aspects of the bill would breach the Withdrawal Agreement that London signed with Brussels, thus breaking international law.
The fear that many, including Biden, have is that any kind of border between Northern Ireland and the Republic of Ireland risks a return of the sectarian violence in the '60s, '70s, 80's and 90's which left more than 3,500 dead.
Biden sent Johnson an unambiguous message in September. "We can't allow the Good Friday Agreement that brought peace to Northern Ireland to become a casualty of Brexit," he said. "Any trade deal between the US and UK must be contingent upon respect for the Agreement and preventing the return of a hard border. Period."
This raises a lot of issues for the UK. A comprehensive trade deal with the US was previously presented as one of the many golden carrots awaiting Brits post-Brexit. This means that Johnson either has to drop his controversial bill, currently going through the UK parliament, or make concessions to the EU in order to strike a formal trade deal. Both would avoid the Biden ultimatum, but both risk making him look weak at home.
With so many differences, at least on the surface, how likely is a good relationship between the President-elect and the PM?
A US official told CNN that all hope was not lost for Johnson. "If you look at the fact Biden is reaching out to Republicans as we speak, I would say that's a good sign for any foreign leader who wants a good relationship with the President-elect."
One concern that has been raised several times in the UK is the prospect of Biden wanting to punish the UK over Brexit, given his and Obama's opposition to it in 2016.
However, Barker points out that although "the Good Friday Agreement is a super red line" for Biden, "he realises he's a transition president and what he is going to do is ensure that these alliances are on solid ground for whatever comes next -- which could even be another Trumpian candidate."
A State Department official appeared to agree, telling CNN that "if David Lammy [an anti-Brexit British lawmaker] can say, 'I didn't vote for it, but I accept this is where we are,' then Joe Biden, who is a foreign policy expert and a pragmatist ... he's going to find a way to make a good relationship with the UK."
It's the not knowing that will concern Downing Street. "We're not pretending everything's OK and going to be dandy," said the senior government figure -- but they see reason for hope.
On Monday evening, Johnson appeared keen to play up the common ground between him and Biden and Harris, particularly on environmental issues.
"One thing that is very exciting that you're already seeing from the incoming administration is their willingness to join the UK in the campaign to tackle climate change," he said. "The UK has been leading in calling ... for countries to get to net-zero carbon emissions by 2050. And suddenly with the advent of President-elect Biden, we're seeing the US really willing to take a lead too on climate change, which I think is great news."
The UK is hosting the United Nations Climate Change Conference next year, as well as taking the presidency of the G7, where Johnson might look to roll out the red carpet. The government figure said "the UK will obviously seek to use the G7 and COP26 to give Biden a platform to set out his foreign policy position."
By that point, Brexit will have been resolved and Downing Street hopes it will have sufficiently convinced Biden that the allies agree in areas ranging from China's hostility to cyber security and interference in elections, so that the US and the UK -- outside the EU -- can forge a new, stronger relationship in areas where that has previously been impossible.
But until Biden finds the time to speak with Johnson, it's going to be a tense wait for the Prime Minister, as he's left to imagine what the next President's first words will be when the two finally get on the phone.