The writer, a former UK cabinet minister and chief economic adviser to the Treasury, is a research fellow at the Harvard Kennedy School

With both Britain and the US under lockdown, and governments in London and Washington struggling to ramp up testing and cope with collapsing economic activity, now is not the obvious time to begin negotiating a free trade agreement.

Yet bilateral talks are getting under way and for both governments there is clear political logic to this. With economic growth plummeting and global trade collapsing, both want optimistic signals to send to the business community. US president Donald Trump, preparing to run for re-election this November, badly needs to show voters his America-first economic agenda remains on track.