But the move was swiftly condemned as commentators highlighted the hypocrisy of someone campaigning for more sovereignty actively seeking another government to interfere in the UK’s affairs.
Labour MP Virendra Sharma of the Best for Britain campaign, said in a statement: “It appears that Kawczynski has today appointed himself as roving Ambassador to Poland. I am sure Warsaw has been waiting for his letter with bated breath.
“I don’t envy Daniel’s burden of self-awareness. Taking back control by asking a foreign government to veto a request made by the sovereign British Parliament is an interesting move.”
Meanwhile, Theresa May is facing fresh challenges in her battle to get Commons approval for a Brexit deal.
Labour has distanced itself from backing a second referendum after tabling an amendment allowing MPs to vote on ways to end the “Brexit deadlock”.
Shadow business secretary Rebecca Long Bailey said the amendment had been carefully written and did not tie the party into backing a new vote “in any way”.
It came as May was due to hold her weekly Cabinet meeting to discuss her next moves, with backbenchers also planning various amendments designed to make various changes on Tuesday.
Labour’s amendment calls for a vote on Labour’s plan for a customs union with the EU, and whether to legislate “to hold a public vote on a deal or a proposition” that is supported by a Commons majority.