Racist groups in Poland are forging links with Neo-Nazis in Britain
Immigration and high unemployment had led to an upsurge in racist activity in Poland, said Dr Krystyna Bleszynska, of Warsaw University.
And groups banned there were cooperating with Combat 18 and other race hate groups in Germany and the US.
Combat 18 takes its name from Adolf Hitler's initials, the first and eighth letters of the alphabet.
Neo-Nazi groups are outlawed in Poland, as they are in many European countries, but there has been growing concern about skinhead activity linked to football hooliganism.
In July, Polish police working with the US Federal Bureau of Investigation (FBI) shut down a neo-Nazi website and charged a man suspected of running it.
The website published details of people on its hate list - such as left-wing activists, homosexuals and members of ethnic minorities, police said.
It was operated by the Polish wing of Blood and Honour, an international group which originated in the UK. The site used a US-based server.
Asked about Polish attitudes to migration at a Commission for Racial Equality conference in central London, Dr Bleszynska said Poland was a "cosmopolitan" and "multi-ethnic" society with a strong sense of social justice.
But there were also nationalists on both the right and left who had racist views.
"In Poland, we have certain legal and illegal organisations acting against immigrants on the basis of racism and that's really very sad," Dr Bleszynska told the Commission for Racial Equality conference in central London.
She said some of the groups were cooperating with Combat 18 in the UK as well as German, Serbian and US groups such as the Aryan Brothers.
Extremist views were not confined to the political margins in Poland, she added.
"Certain groups of nationalists, which also display also racist attitudes, act in the frame of legal organisations.
"You can find them in the right wings of our parties, or strong left wings, for instance in the League of Polish Families you can meet some political leaders who are nationalistic and racist," Dr Bleszynska said.
Poland had been a multi-ethnic country for centuries, with immigrants from the Ukraine, Belarus and elsewhere, but it had only very recently become a multi-racial society, with the arrival of immigrants from Asia, she said.
Average unemployment was 16% but it was 25% among young people and immigrants were sometimes seen as "people who will take Polish jobs".
Some Polish migrants in the UK, meanwhile, were being supported in their "unpleasant" behaviour by British nationalist and Neo-Nazi groups, said Dr Bleszynska, who is professor of multicultural education at Warsaw University.
Many Poles were highly qualified and found it easy to find work in the UK, Dr Bleszynska said.
But others, who were less well-educated, sometimes found it difficult to find jobs and were not accustomed to the multiracial nature of British society.
In particular, they found it difficult to understand "positive discrimination," which they viewed simply as "negative discrimination".
In areas such as Ealing, in West London, Polish "ghettos" were forming, Dr Bleszynska claimed, with some young Poles unable to find work but also unable to return home.
"They are ashamed to come back to tell their friends and family, I am sorry I was not successful," she said.
They sometimes faced "very unpleasant behaviour" when competing for jobs with British people, she said, but their behaviour in response was "also not pleasant".
And they were being "supported by British nationalists and Nazi groups," she added.
About 600,000 people have come to work in the UK from eight nations which joined the European Union in 2004, according to official figures, with the majority, about 447,000, coming from Poland.
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