If the U.K. fails to leave the European Union, then Britain's entire democratic system would be under attack, the opposition Labour party's Kate Hoey told CNBC Thursday.
Hoey, a pro-Brexit member of Parliament for a pro-Remain constituency in London, pointed out that the British people voted to leave the EU at the 2016 referendum — they were not voting on whether they wanted a deal with the bloc.
"The delay that people are pushing for is really being pushed by people who want to overrule the result of the referendum," she told CNBC's "Squawk Box."
"Parliament gave a very clear instruction: 'Your vote will be counted. It matters. If you vote Leave, we will leave.' We have to do that, otherwise our whole democratic system, I think, is under real attack."
She spoke to CNBC after British Prime Minister Boris Johnson failed in his bid to call a snap general election on Wednesday, after lawmakers took control of Parliament this week and voted through a bill that aims to stop a no-deal Brexit. Hoey was one of a few Labour MPs who voted in favor of snap elections.
In a no-deal Brexit scenario, the U.K. would leave the EU without a deal in place. It would be an abrupt departure, without any transition period for businesses based in Britain to adjust to life outside the bloc.
New legislation to stop a no-deal Brexit was passed by a vote of 327-299 on Wednesday and could now essentially force Johnson to ask the EU for another delay for the U.K. departure, which has a current deadline of Oct. 31. The EU would have to agree to a delay and the bill would also have to be approved by the largely pro-EU House of Lords — the upper house of parliament — later this week.
Hoey said that Johnson is "determined to honor the will of the British people."
Asked if she thought the British people could've changed their minds about Brexit since the initial vote, she said people have become more aware of just how "anti-democratic the European Union is. And, how restrictive it has made some of the ways that a country can trade independently."
In fact, she said, if there were another referendum, even more people would likely vote to leave.
Economic consequences and the Irish backstop
Many analysts have said that if the U.K. departs from the EU without a deal in place, it could usher in a period of prolonged and severe uncertainty.
A report this week said the imposition of tariff and non-tariff barriers between Britain and its largest trading partner will be a major shock to the economy, while sterling's predicted decline will drive up inflation and reduce real wages. That disruption, according to the report from academic think tank The U.K. in a Changing Europe, may not be immediate since there are contingency plans that have been implemented by the government and businesses.
But others have said that the U.K. economy may be in a better shape than most people think it is, and that would allow it to cushion the negative impact of a no-deal Brexit.
One of the biggest hurdles in ongoing Brexit negotiations between the U.K. and the EU is the matter of the Irish backstop, the border that separates Northern Ireland and the Republic of Ireland.
For her part, Hoey said plenty of work is being done by different groups to find ways to prevent the establishment of a hard border. "The Republic of Ireland has different excise duties, different corporation taxes, different VAT, has different currency. All of these things are different already and we manage that quite well," she said.
"There's absolutely no reason, with goodwill, why we cannot sort this with technical solutions and various customs experts have said so," Hoey added. "The reality has been that the European Union has seen the Irish border as a very useful way of trying to keep the United Kingdom in the customs union."
— CNBC's Matt Clinch contributed to this report.