LONDON (Reuters) - Facebook Group was hit hard on Thursday by the European Court of Justice, which ruled that national courts in Europe could order online platforms to remove defamatory material around the world.

The decision is a triumph for EU stakeholders, who aspire to force US technology giants to meet European standards on hate speech and offensive content.

Last week, the same court ruled that Google was not required to apply the "right to forget" online to its search engines outside Europe, in a landmark decision that would be a victory for the American group.

In a forthcoming ruling, the court said European laws "do not prevent" courts from deciding "to remove information or withhold access worldwide."

The case is due to a lawsuit filed by Austrian Greens political party Eva Glafishnig in an Austrian court demanding the removal of Facebook posts that the judges decided they defamed and could be read on the site around the world.

The lawsuit includes leaflets from fake accounts that described Glashishnig as "corrupt" and Facebook refused to remove.

A higher Austrian court referred the case to the European Court of Justice for opinion and sentencing, which cannot be challenged, which will be used as a reference across Europe.

Under this decision, Facebook or similar platforms such as Twitter will have a greater obligation to monitor content posted on their platforms and remove any offensive content or hate speech even from fake accounts.

Facebook condemned the European Court's ruling, saying it "undermines the long-held principle that one state cannot impose its laws on expression on another."

It also deplored its obligation to pursue "similar" content that repeats insults or hate speech.

"In order to obtain such a right, national courts must establish very clear definitions of identical and 'similar' meaning in practice," it said in a statement.

"We hope that the courts will take a coherent and calculated approach to avoid having a frightening impact on freedom of expression."

Austrian politician Glafishnig, in turn, praised her decision as a “historic success of human rights against the Internet giants”.

According to the Austrian news agency, the decision "does not violate the freedom of opinion in any form."

Transitional EU judgments on hate speech are limited.

So far, Internet giants such as Google and YouTube have voluntarily agreed to remove insulting content or hate speech, including those linked to terrorism, within 24 hours.

But the EU is expected to impose tougher trans-European measures, including fines, if Facebook fails to comply with court orders.