By William Schomberg
LONDON, Sept 23 (Reuters) - Mark Carney has been taking the big decisions for Britain's economy for the past three years, but his next one will be much more personal.
The Canadian has said he intends to say before the end of this year whether he will stick to his original plan to step down as Bank of England governor in less than two years' time, or extend his stay until 2021.
Above all, he will have to decide whether he wants to stay for the task of steering Britain's economy through what is likely to be a period of upheaval as it leaves the European Union and begins life outside the bloc.
Some think that is the kind of job that Carney - who was hailed by the man who hired him, former British finance minister George Osborne, as the "outstanding central banker of his generation" - would relish.
When his move from the Bank of Canada to the BoE was announced in 2012, Carney said he was "going to where the challenges are greatest" at a time when Britain was still suffering from the hangover of the global financial crisis.
Richard Barwell, a former BoE economist, said the even bigger challenge of Brexit would appeal to Carney's sense of ambition. "He wants to be in the spotlight and on the world stage," Barwell, who now works at BNP Paribas, said.
Even if he privately has doubts about staying, Carney might find it hard to leave London after five years, given the expected Brexit shock to the economy. "Walking away at time of crisis might not be seen as the done thing," Barwell said.
When Carney agreed to come to London, he secured an agreement from Osborne that he would run the BoE between 2013 and 2018, with an option to serve out a full eight-year term if he wanted to take it up.
Carney, the father of four school-age children, said then that he had personal and professional reasons for staying for five years rather than eight.
He quickly began an overhaul of the 322 year-old BoE, making its monetary policy and bank supervision work more closely, addressing one of the key lessons of the financial crisis.
But in January, Carney left the door open to a longer term, saying he would decide by the end of this year whether he would seek to stay until 2021.
Commentators were quick to link the change in tone to the diminished prospects of a switch into politics for Carney in his native Canada, where Justin Trudeau had just been elected as the country's new, young prime minister.
Under the terms of his appointment, Carney can choose to serve out the full eight years without the approval of Britain's new finance minister Philip Hammond who, in any case, has said spoken highly of the BoE's smooth response to the Brexit shock and said Carney was doing "an excellent job."