For decades, immigration has been one of the key debates in British public life. The latest European refugee crisis, however, has pushed this debate even further into the spotlight. If a tough anti-immigration speech given by a top government official is any indication, the issue isn't going to go away any time soon.

Speaking at the annual Conservative party conference on Tuesday in Manchester, Home Secretary Theresa May defended Britain's plan for resettling Syrian refugees from camps in the Middle East, a scheme that means opting out of a European Union plan designed to fairly redistribute refugees. Britain would not accept an E.U.-wide immigration and asylum policy "in a thousand years," May explained.

May also argued more generally against the value of immigration. "Britain does not need net migration in the hundreds of thousands every year," May warned, arguing that evidence showed "at best the net economic and fiscal effect of high immigration is close to zero."

The home secretary also warned that when immigration was too high, "it’s impossible to build a cohesive society."

In a bid to prevent abuse, May announced that Britain would reform its own asylum policy. Refugees who have "spurned the chance to seek protection elsewhere" – having traveled through Europe, for example – would not have an automatic right to stay in Britain. A new system of "safe return reviews" would be implemented so that asylum seekers could eventually return home.

While the speech drew the support of British Prime Minister David Cameron and the right wing UKIP ("PM and Theresa May have both echoed UKIP almost verbatim this morning," the party tweeted), the reaction from other wings of British society was often critical.

Simon Walker, director general of Britain's Institute for Directors, said he was "astonished by the irresponsible rhetoric and pandering to anti-immigration sentiment from the home secretary." The Refugee Council, an organization that works with refugees and asylum seekers, specifically criticized the new asylum plans. "Every asylum claim must be judged on its own merits," the organization said in a statement. "No one is in a position to pre-judge the validity of someone’s asylum claim before they’ve had the chance to make it."

Surprisingly, some of the most blistering criticism came from center-right publications. James Kirkup, deputy political editor of the Telegraph, was one notable example. "It's hard to know where to start with Theresa May's awful, ugly, misleading, cynical and irresponsible speech to the Conservative Party conference today," Kirkup wrote, pointing to Britain's strong economy and government reports suggesting immigrants were not displacing UK natives from the labor market.

That sentiment was echoed by Alex Massie of the Spectator, who accused May of a "stale and noxious concoction of tawdry nativism" and ignoring the positive influence immigration had on London.

With Cameron widely expected to step down as leader of the Conservative party before the next election in 2020, speculation has been growing about who might succeed him with many viewing May as a potential successor. May's speech appeared to put show she was following a harder line on immigration than the British prime minister. It could possibly be a wise move for the home secretary – polls have shown British voters consider immigration to be most important issue facing the country, with many wanting to leave the E.U. over concerns about immigrants.

More on WorldViews

David Miliband: The refugee crisis is here to stay

The forgotten story of when the Germans were the refugees