(JTA) — A recent poll that found nearly 40 percent of British Jews would leave the country if Labour Party leader Jeremy Corbyn came to power “sickens me,” British Prime Minister Theresa May said.

“I do not underestimate the threat posed by those who promote anti-Semitism, or hatred in any form. Nor the pernicious nature of what those people say and what they stand for,” May said Monday at a United Jewish Israel Appeal dinner in central London.

“But I do not believe those voices speak for the vast, overwhelming majority of people in our country. … And most importantly, I do not believe that those voices will ever win. We will not let them win,” she told the audience of 800.

The poll appeared earlier this month in the London-based Jewish Chronicle.

“If we are to stand up for the values that we share, then one of the things we need to do is give young Jewish people the confidence to be proud of their identity – as British, Jewish and Zionist, too,” May said.

She offered her support to the British Jewish community and to Israel.

“I have come here tonight as prime minister of our country to say that I stand with you,” May said. “I stand with Israel as the homeland of the Jewish people. And I stand with the entire Jewish community in Britain.”

May alluded to the fact that the Labour Party adopted the International Holocaust Remembrance Alliance definition of anti-Semitism after delaying the vote, but only after adding a free-speech clause on Israel.

She stressed her government’s adoption of the full IHRA definition.

“Criticizing the actions of Israel is never – and can never be – an excuse for questioning Israel’s right to exist, any more than criticizing Britain’s actions could be an excuse for questioning our right to exist,” the prime minister said.

“And criticizing the government of Israel is never – and can never be – an excuse for hatred against the Jewish people, any more than criticizing the British government would be an excuse for hatred against the British people.”