Revealed: secret cross-party summit held to confront failings of Brexit

Those in attendance from the pro-Brexit side included the former Tory party leader Michael Howard, former Tory chancellor Norman Lamont and former Labour Europe minister Gisela Stuart, one of the leading figures of the leave campaign.

Among the prominent remainer politicians present were shadow foreign secretary David Lammy, shadow defence secretary John Healey and the former European commissioner and Labour cabinet minister Peter Mandelson, who acted as chairman. From the Tory remainer camp, the ex-cabinet minister and long-serving minister for Europe, David Lidington, attended.

Non-political attendees included John Symonds, chair of the pharmaceutical company GlaxoSmithKline; Oliver Robbins, Goldman Sachs managing director and former chief Brexit negotiator for the government from 2017 to 2019; Tom Scholar, the former Treasury permanent secretary; and Angus Lapsley, Nato assistant secretary general for defence policy and planning.

The unresolved matter of the Northern Ireland protocol, which is the main UK-related subject currently occupying EU officials in Brussels, was also central to the talks.

Concern is growing at the top of the Labour party that it poses a real threat to the success of any future Labour government unless problems such as increased trade friction can be addressed.

For those such as Gove who campaigned to leave the EU, there is also a clear interest in ensuring Brexit is not viewed as a failure over the long term, even if this means conceding that there will need to be closer engagement with the EU.

Labour, which has said it will not take the UK back into the EU, the single market or customs union, has, however, already committed to using the 2025 review of the TCA to try to reduce barriers to trade.