Chancellor Gordon Brown has warned business leaders of the dangers of "head in the sand" protectionism.
Chancellor Gordon Brown will address the CBI
In a speech to the CBI in London, he has stressed that economic patriotism by European countries means they are failing to create a single market.
He sees the fact that some European countries have blocked recent cross-border corporate takeovers as a sign that such patriotism is growing.
His comments come ahead of meetings of EU and G8 finance ministers this week.
Ahead of his speech the chancellor said Britain could become one of the "great success stories" of the global economy, perhaps "more successful than we were in the 19th Century".
He argued that for a small country like Britain, success depended on ensuring the talents of every individual were harnessed.
"You can be part of the global economy but have a huge pride and patriotism about your country," Mr Brown told BBC Radio 4's Today programme.
Asked about immigration, he said it was vital that there were proper controls and that people coming to Britain should learn to speak English and respect UK laws and traditions.
But he stressed the benefits to the British economy from people such as foreign undergraduates who opted to study here.
"I think people who come into this country, who are part of our community, should play by the rules," he said.
"I think learning English is part of that. I think that understanding British history is part of that. That's why I want to see changes in the curriculum.
"I would insist on large numbers of people who have refused to learn our language that they must do so."
Costs of protectionism?
Mr Brown went on to warn that the European Single Market was being undermined by "economic patriot policies" being pursued by some EU members.
"The danger is that the world relapses into another bout of protectionism which would mean less trade, less growth, less exports, less jobs. We have got to fight that both in Europe and round the world," he said.
Europe needed to "wake up to the costs of agricultural protectionism" and the "restrictive practices" of some nations which were hampering the growth of the single market.
"The future for Britain, which makes me incredibly optimistic about the future if we make the right decisions, is incredibly bright but we have got to prevent the retreat into protectionism," he said.