The MP for Shrewsbury and Atcham revealed he had spoken to the Polish government after it emerged Prime Minister Theresa May had asked for a three-month extension to Article 50, the mechanism where Britain leaves the EU.
The UK is due to leave the EU on Friday next week, but the extension would push Brexit back to the end of June.
However, Mr Kawczynski said he had little expectation that his intervention would have any impact, saying that the European Commission operated like a 'Mafia cartel' which nation states were afraid to stand up to.
"As a fluent Polish speaker, and somebody who knows many people in the Polish government, I recently went back to Poland to ask the government to formally veto any extension to Article 50, as it is not in the interests of the EU or the Polish economy to have a delay," he said.
"I would very much doubt if, following these discussions, any European government would veto this extension, because the EU Commission operates as a Mafia cartel – when you speak to the national governments, they sound sympathetic, but when it comes to the vote, they are frightened to go against the EU commission."