The old Etonian foreign secretary got other EU ministers into a boat with him at a mini summit at official grace and favour mansion Chevening House.
The event saw him hold talks on European security with counterparts from eight countries, Bulgaria, Croatia, Czech Republic, Hungary, Poland, Romania, Slovakia and Slovenia.
He told them: “Our departure from the EU will make no difference to Britain’s unconditional and immovable commitment to the security and defence of Europe.
“This meeting was a further demonstration that the UK is a vital partner in the security of our continent.”
The meeting came as the UK secured fresh sanctions from the EU against North Korea to ramp up pressure on the regime’s nuclear weapons ambitions.
Foreign ministers meeting in Luxembourg will back plans to cut off sources of cash that prop up Kim Jong-un’s nuclear missile programmes.
A ban on EU investment into the rogue state will be expanded and exports of European oil ended.
More names will be added to the list of regime officials and companies that are hit by asset freezes and travel bans.
A review of the banned luxury goods lists will be carried out and the cap on personal payments sent to North Korea reduced from 15,000 to 5,000 euro.