British conservative leaders called for further immigration crackdowns this week after EU travel restrictions on Bulgarian and Romanian workers were eased.

With Britain's coalition government already facing pressure from political leaders such as London Mayor Boris Johnson and Nigel Farage of the U.K. Independence Party to greatly increase the waiting time for immigrants to receive benefits, a new survey was released Monday indicating widespread support for severe curbs on immigration.

The debate was sparked when the European Union on Jan. 1 lifted seven-year transitional restrictions on the free movement of workers from Bulgaria and Romania throughout the whole of the EU after the Balkan nations' 2007 accession to the bloc.

With the restrictions lifted, Bulgarians and Romanians no longer have to apply for special work permits for some job categories in Britain.

The date was met with alarm by conservatives, who discounted the EU's assertions it wouldn't trigger a mass migration. They pointed to a gross underestimation of the number of Polish migrants who flooded into Britain following a similar easing of restrictions in 2004.

Bulgaria and Romania dispute that scenario, saying most of those seeking to work in Britain and other EU countries have already left to do so. Some 3 million Romanians and Bulgarians work and live other member states.

Brussels contends such migrants contribute more to a country's tax base than they take out, strengthening the economy of the host country. However, critics assert many such workers come to Britain as "benefits tourists," claiming benefits for children living outside the country.

Under new regulations authored by Prime Minister David Cameron and approved by Parliament last month, migrants from all EU states will have to wait three months before applying for child support and other out-of-work benefits.

But Johnson, London's Tory mayor, said Monday that wasn't long enough, calling for a waiting period of two years, the Independent reported.

"We don't want to be slamming up the drawbridge being completely horrible to people," he said. "If you want to come and work here you can do that but there should be a period before which you can claim all benefits and it seems entirely reasonable to me that they should extend that to two years."

Farage of the right-wing U.K. Independence Party went further Monday, calling for a five-year ban on all permanent immigration.

Meanwhile, a new survey indicated 77 percent of Britons now believe that the number of new arrivals should be reduced either "a little" or "a lot" -- marking an all-time high favoring restrictions on the question since 1995.

The British Social Attitudes survey of 3,243 Britons, however, also found respondents were less likely than in 2011 to believe that immigration was bad for the economy, falling from 52 to 47 percent -- indicating acknowledgment of migrants' economic contributions.

But Farage said the social trade-off isn't worth it.

"I do think the social side of this matters more than pure market economics," he said. "I would rather we weren't slightly richer and ... that we had communities that felt more united and a situation where young unemployed people had a realistic chance of getting a job."