We report that the chancellor's claim that Britain would have a sovereign wealth fund worth "probably a trillion pounds" had it invested North Sea revenues from the 1980s rests on internal Treasury modelling. The BBC reports that the modelling has not been published.
According to the BBC, the modelling assumes £200bn of historical North Sea receipts were invested with no withdrawals and grew at a rate comparable to Norway's. The figure is roughly double a 2018 estimate by the Institute for Public Policy Research, which put a fund begun in the 1980s at more than £500bn.
The remark came as the government approved the Jackdaw gas field on 21 October and announced a £2bn Energy Wealth Fund.
Read our report: Chancellor says saving North Sea oil revenues would have built £1tn wealth fund