Bank of England governor Mark Carney would have been poorly placed to handle the fallout from a no-deal Brexit had he left the role in June next year as previously planned, Britain's finance minister Philip Hammond said on Tuesday.
Hammond made the announcement while speaking at the Parliament.
The decision also raises questions about the government's grasp of the Brexit process if Carney's presence is needed to ensure stability, or the United Kingdom treasury is struggling to find a replacement while it focuses on negotiations.
He will now remain in post until January 2020.
A senior government figure said: "The PM thinks he has done a good job in hard circumstances; he is well respected and has a good worldwide standing".More news: Jurgen Klopp scoffs at Gary Neville's suggestion
"Accordingly, I am willing to do whatever I can in order to promote both a successful Brexit and an effective transition at the Bank of England".
"It is an important time and we have an important supportive role to make sure whatever Brexit the government negotiates, it is a success, and providing a measure of continuity should help that".
"In a sea of Brexit political pygmies the governor of the Bank of England is one of the only sane voices at the table, so it is welcome news he is staying on".
Last November the BoE raised rates for the first time in more than a decade and increased them again last month, when Carney said that market expectations of a further rate rise a year for the next few years would be a reasonable rule of thumb. Following Britain's Brexit vote, he agreed to remain in place an additional year to the end of June.
"He will install a measure of certainty on monetary policy, which provides some air cover through what will surely be an unpredictable spell".