Labour MP Kate Hoey has said she believes Brexit has "completely broken" the two-party system.
The pro-Brexit campaigner told talkRADIO's Julia Hartley-Brewer that staunch Leavers and Remainers were unlikely to vote Labour or Conservative in the upcoming EU elections.
"I said a month ago when the Brexit Party was set up that I thought both Labour and Conservatives would be trounced at the European elections, and I still feel that," she said.
"It is going to almost become another referendum in a way, because I think what we'll see is those who feel strongly about leaving will not vote for either of the two parties, and those who feel strongly about remain will not vote for either of the two main parties."
She continued: "It will tell us that the two-party system on this issue is completely broken. It will tell us that the country is very angry - whether they're Remainers or Leavers - that we haven't got on with this."
Ms Hoey continued to say that she felt as though British politics had become a "dictatorship", with Theresa May refusing to name her resignation date.
However, she said if the Brexit Party were to win the Peterborough by-election - triggered after constituents demanded the removal of independent MP Fiona Onasanya - it would be "untenable" for Mrs May to continue in her role.