He says that since Britain must prepare for a "paradigm change", in the economy, any assessment in the automotive, aerospace financial services or other sectors would fail to be "informative".
Philip Hammond, widely viewed as the most pro-European of Prime Minister Theresa May's senior colleagues, said in a speech at the annual dinner of finance association CityUK that future trading arrangements with the European Union had to be "durable and fair".
"We have made a lot of progress over the last weeks".
Britain has yet to start serious trade talks with the European Union ahead of its March 2019 departure, as the process is now bogged down in disagreements over border arrangements between the British province of Northern Ireland and the Irish Republic.
"This political ping-pong battle is really hurting investor sentiment towards sterling", said Neil Jones, Mizuho's head of currency sales for hedge funds in London.
The pound dropped sharply and then bounced.
Annual economic growth speeds up to 2.8pct
Meanwhile, spending on electricity, gas and other fuels went up 11.5 per cent and cigarettes and tobacco went up 11.1 per cent. The figures highlighted the two-track nature of Australia's recent economic growth.
Failure could mean a delay until February, adding to the risk of businesses scaling back investment plans in Britain as uncertainty clouds the outlook beyond Brexit in March 2019.
Optimism drove sterling to six-month highs on a trade-weighted basis last week, and it traded around 0.4% below those highs this morning.
Against the euro, sterling weakened 0.4 percent to 88.35 pence.
More pain could be on the way for sterling should Brexit talks stall further, according to a note circulated by Capital Economics to clients on Wednesday morning.
Selling calls ensure a steady premium income for trading desks but also reflect a growing view that it is unlikely to rise to those levels.
Sterling has had an up and down week so far, swinging wildly between losses and gains as investors try to make sense of the latest developments in the United Kingdom and EU's Brexit negotiations.