THANKS TO what he described as the 'toot of the cavalry bugle' in the distance, with the arrival of a Covid vaccine, this has been a rare better week for Boris Johnson. But while that might be the case over coronavirus, things are still stacking up against him over Brexit, the issue he used to ride to power.

Like a gambler whose pile of chips is getting smaller, he has few left to play as the game continues. A lot of his diminishing pile was bet on his friend and ally, Donald Trump, winning the US election and celebrating with promises of a trade deal with the UK to leave Europe out in the cold. Instead Johnson had to grab what credibility he could because he was number two, after the Canadian prime minister, on the list of heads of state Joe Biden called after becoming president elect. That may be down to timing of the list of calls to be made more than anything else, but the conversation will not have been comfortable.

Biden is no enthusiast for Brexit, unlike Trump, because he does not see political mileage in dividing Europe. As someone proud of his Irish heritage, Biden is also opposed to any Brexit outcome that might have a negative impact on the Good Friday deal and peace in Ireland. That message to Johnson will have been loud and clear in that phone call.

It was also echoed this week when the House of Lords and every former Conservative prime minister rejected the government's Internal Markets Bill. It claims this is to maintain the integrity of the UK if it does not get the Brexit deal it wants. But there is no escape from the reality that what it does is position the UK to break an international treaty. That tactic might have been acceptable to Trump, but it will never wash with Biden or indeed most other countries with which the UK wants post-Brexit trade relationships.

Johnson will also have learned, yet again, the lesson that he needs to be more careful with his words. In 2016, when he was campaigning for a no vote in the EU referendum he attacked Barack Obama for pouring cold water on a post-Brexit trade deal with the US. He suggested Obama, because of his Kenyan roots, had an 'ancestral dislike' of the British Empire.

Those words have come back to haunt Johnson now as he seeks a trade deal with the US. Biden was Obama's vice president and some of his political allies continue to deem the comments racist and more worthy of Trump than a British prime minster. How serious that is for the mood music of the UK/US relationship time will tell, but there is no escape from the reality that a trade deal is now less likely than before the US elections.

This has narrowed Johnson's options. He can do a deal with the EU or seek to go it alone with no significant global trade ally. The former is now his chosen option and while the bluster about walking away with no deal is still there, the Downing Street tone to Brussels is more conciliatory. This was clear after Johnson spoke with the European Commission president, Ursula von der Leyen, which ended with both confirming their commitment to finding a deal. Indeed if there has been a toughening of stance this week it is on the European side, mainly because it believes the loss of a potential US trade deal with Trump has weakened the UK negotiating position. Like other gamblers watching at the table it can see Johnson's pile of chips shrinking.

Some form of words that will maintain 'business as usual' after December has to emerge soon. The talking around the detail will however continue. The positive feeling now around a Covid vaccine may be a good opportunity for the government to bury bad Brexit news for many of its supporters.

Watch out for concessions from the EU on fishing, which will be more about optics than substance, while the UK gives way on other issues. For agriculture this would be a sensible outcome. It would bring some much needed certainty about the relationship with our biggest trading partner. The EU is now the word's biggest trading bloc, with 15% of global trade. That is key to the future for farming, while any trade deal with the US would end up one-sided against the UK for mainstream agricultural products.