“The sums I have seen that they propose to demand from this country appear to be extortionate,” Johnson told lawmakers in Parliament on Tuesday.
“Go whistle seems to me to be an entirely appropriate expression,” he added. The phrase go whistle means to ask for something with little chance of obtaining it.
The European Union has demand tens of billions of euros from Britain as part of its “Brexit bill” before Brussels launches talks on a free trade agreement with London.
Reports have suggested the demand from the EU could be as high as 100 billion euros (84.58 billion pounds). The UK government has said it will not pay this amount but will settle its “obligations” as it leaves.
Nearly 52 percent of Britons opted to leave the bloc during the EU referendum in June last year.
The United Kingdom formally triggered the Brexit process on March 29 and divorce negotiations officially began on June 19.
Prime Minister Theresa May has made it clear that if the two sides miss the deadline without achieving a deal she would take the country out of the EU regardless, raising the prospects of a so-called “hard Brexit.”
“For the government to threaten to leave the EU with no deal, while boasting about not having a plan for that eventuality, is completely unacceptable,” Labour MP Chris Bryant told the BBC last month.
Johnson told MPs not reaching any Brexit arrangement with the EU was unlikely as it was in the interests of both sides to reach an understanding. “There is no plan for no deal because we are going to get a great deal.”