American technology giants including Google, Yahoo and Amazon have been criticised by privacy groups and European regulators for lobbying in Washington against new EU data privacy laws.
The American firms are campaigning for more relaxed data laws in order to make it easier for them to pass on information for their business operations.
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However, the EU is looking to introduce laws that make restrictions on such exchanges of information tighter, potentially putting lawmakers in the bloc and the US on a collision course.
But US privacy groups including the American Civil Liberties Union and the Liberty Coalition have written to senior figures including Attorney General Eric Holder and Secretary of State John Kerry urging them to support European data protection laws.
"Our personal data - our privacy - is being abused by both the commercial sector and governments. In fact, the line is increasingly blurred as personal data passes between both with few restrictions," said the letter.
"Europeans are working together to update and modernise their framework for privacy protection. There are many important, innovative proposals contained in the package of reforms, as well as the recognition that the process of data protection can be simplified to the benefit of all," it continues.
The letter adds that its authors support the EU's efforts and suggests "promotion of stronger privacy standards in Europe will benefit consumers around the globe, as businesses improve their privacy practices and security standards."
Meanwhile, speaking to The Financial Times, Jacob Kohnstamm, head of the Article 29 Working Party representing EU privacy regulators, said European legislators are "fed up" with American companies putting their interests ahead of human rights.
He argued that if European companies lobbied the US government in a way that the likes of Google and Facebook are doing in Europe, they would quickly be shown the door.
"If such a lobby from the European side were organised towards Congress, we would be kicked out of there."
The European Parliament is scheduled to vote on first draft legislation of the data privacy laws at some point in April.