In a case that pits privacy and the "right to be forgotten" against the right of free speech, the European Union's top court is expected to issue a landmark ruling on Tuesday that will determine whether Google must remove links to sensitive personal data worldwide or just in Europe.

In a second related case, the Luxembourg-based European Union Court of Justice will also rule on whether links to websites that contain allegations about individuals' sex lives or criminal records should also be removed.

The rulings are seen as a test case of the tensions rising worldwide between the protection of an individual's data and freedom of speech. They also highlight the clash between EU regulators and U.S. tech companies.

The first case stems from a dispute between Google and France's privacy watchdog, CNIL, which in 2015 told Google to remove sensitive information from internet search results globally when asked to do so, in accordance with its 'right to be forgotten' law.

Google challenged the ruling, and the French court turned to the European Court of Justice for guidance.

In January of this year, Google welcomed the news that EU advocate general Maciej Szpunar had issued an advisory opinion to the EU Court, saying the right to be forgotten should only be enforced in Europe and not globally. Judges often follow such non-binding opinions, but not always.

The legal conflict has broad implications for the fate of the internet, at a time when the world is increasingly focused on privacy protections.

"It creates a huge clash between the irresistible force of EU data protection law and the immovable rock of U.S. freedom of speech," said Peter Church, a privacy expert at Linklaters in London.

But if U.S. citizens were to be prevented by EU data protection laws from seeing search results, it would be "a step too far", he said.

Currently, Google in Europe has to remove all links that appear in its global search results if individuals ask them to be deleted under EU data protection rules. According to a Google report, the company removed 45% of the 3.3 million links from 845,501 requests received in the last five years – since the 'right to be forgotten' law took effect in Europe in 2014.

But that law left open the question of whether the right to be forgotten only applied in the EU or was a global right. This is what the EU Court of Justice is expected to decide on Tuesday.

Meanwhile, Google has been using geoblocking technology in the EU's 28-member bloc to remove links to information that breaches EU data laws. But users outside the EU can still see the contested results.

In a separate but connected case, the EU court has also been asked to rule on whether links to websites that make damaging claims about individuals' sex lives or criminal records should also be removed.

Four individuals had asked CNIL, the French data protection authority, to demand that Google remove the links found in internet searches using their names – a request the French agency rejected. The material in question included a satirical photomontage of a female politician; an article referring to someone as a public relations officer of the Church of Scientology; the placing under investigation of a male politician; and the conviction of someone for sexual assaults against minors.

In his advisory opinion issued in January, the advocate general said that prohibitions on processing certain types of data should also apply to the operators of search engines.

While in the U.S. freedom of speech usually takes precedence, judges in London and Paris have ruled in favour of individuals asking to have unflattering information removed or suppressed in internet search results.

Google, which is the leading search engine in Europe, is also facing other obstacles in Europe. The European Commission has fined the company billions of euros for antitrust violations.