The nationalists hope to gain more political impact by uniting
The British National Party (BNP) has joined forces with far-right groups in a new European Alliance of National Movements.
The movement will not be recognised as a political bloc in the European Parliament, but it might receive EU funding as a pan-European grouping.
BNP leader Nick Griffin - one of two Euro MPs from the party - said the funding would be 11m euros (£10m).
French and Hungarian nationalists are heading the alliance with the BNP.
Fellow MEPs Bruno Gollnisch of the French National Front and Balczo Zoltan of the Hungarian Jobbik party launched the new movement in Brussels, alongside Mr Griffin.
They do not meet the EU minimum requirement for recognition as a political grouping in the parliament - that is at least 25 members from seven countries.
The BBC's Dominic Hughes in Brussels says the new alliance will have to satisfy complex EU rules to gain access to EU funding.
Jobbik runs a nationalist group called Magyar Garda (Hungarian Guard)
He says there is also a question mark over how well the new allies can work together, since an attempt to form a similar group in the previous parliament - known as Identity, Tradition, Sovereignty (ITS) - collapsed in November 2007.
Among the conditions set by the European Parliament for funding pan-European political parties is a clause saying they "must observe the principles of liberty, democracy, respect for human rights and fundamental freedoms, and the rule of law".
The new alliance's manifesto, published on the National Front (FN) website, says it "rejects all attempts to create a European superstate".
It calls for "a humane and peaceful solution to the problem of immigration" through co-operation to raise living standards in developing countries.
It advocates "effective protection of Europe against the new threats of terrorism, as well as against political, economic, financial or religious imperialism".
It calls for "strong pro-family policies to reverse Europe's population decline and to promote traditional values in society".
The alliance also wants a "joint fight" against "the destructive effects of globalisation".