They're downplaying reports of infighting at Downing Street after the resignation of one of Boris Johnson's key aides.

The upheaval at the heart of government comes as ministers grapple with the pandemic and concerns over a post Brexit trade deal.

With 50 days to go until the end of the transition period, there's a warning from the Irish T shock that the UK must knuckle down to agree a deal with the European Union is our political editor Laura Kingsburg reports Boris Johnson's in charge because of Brexit.

He wants to change how we deal with the rest of the world.

But there's been meltdown among his band of brexiteers.

And if there is no trade deal, that could be economic turmoil to so Michael Gove's warning business to be prepared, agreement or not, by choosing to leave the European Union, we became a sovereign equal on.

It's absolutely important that the you recognize that I think the penny is dropping it is, is it not rather extraordinary that with only a matter of a few weeks ago, you cannot tell businesses, particularly in Northern Ireland, how they're going to have to trade?

There are still some things which do need to be resolved.

This deal will set the terms of our relationship with the U for years to come.

That's why it's so important to get it right.

You've got people in government fighting like rats in a sack.

Now what kind of impression does that give to people desperately worried about maybe not being a trade deal?

There's a complete focus in government on making sure that we can work with business and work with citizens in order to deliver on the promise of Brexit on to take advantage of the opportunities of being outside the European.

And you say that with a straight face like prime minister because even choose a chief of staff.

Well, what I do every day and what the prime minister does every day is ensure that we're delivering on the manifesto pledges that we were elected on last year.

But is a shakiness toe everything because they've seen tremors and big moves in there.

Watch this.

The prime minister's longest serving Brexiteers aid Lee Cain walking out of his job, in part because the new press secretary, Allegra Stratton, enjoying arriving at the front the position of the most controversial advisor Dominic Cummings is now perhaps in question is about for the country.

Have tension in Downing Street, Mr Coming just as one of the most important moments for their Brexit project arise 10 days or so left to do a trade deal with the EU.

It's patients.

Brussels chief negotiator in London talks in stalemate With hardly any time to go Other leaders in the U R origin Boris Johnson to budge to get a deal done, especially from Dublin, where the effect of a bust up would be so acute.

We've all had a very significant shock to our economic system because of covert 19.

The last thing we need now across all of our respective economies is a second major shock that a no deal would cause.

Many people in the U.

K government just don't believe that the U is ready to compromise enough In all negotiations.

Both sides take positions both sides have to move, and all negotiations, if I could, respectfully said that's what British government should head in that direction.

In my view, it should knock it down and start get a deal with the European Union on the first of January.

Whatever happens the way we trade with and interact with our neighbors.

On the whole, you will change in some very big ways.

If politicians can put aside their differences and do a deal, that transition will be significant but smooth.

But if the politics fail on an agreement, just can't be reached.

There could be big disruption on outline of the trade deal can be seen on both sides, but the final act of the Brexit project isn't over.

Laura Ginsburg, BBC News.