Attacking journalists and prosecuting critical voices fuels violent extremism rather than preventing it, the United States told the United Nations Security Council on Wednesday in a thinly veiled warning to Egypt, which chaired the meeting.

"Arresting journalists, sentencing reporters to death, treating media as an enemy of the state - such actions are thoroughly counterproductive," said the US Ambassador to the United Nations, Samantha Power.

Amid rising dissent against Egyptian President Abdel Fattah al-Sisi, police earlier this month raided the country's press syndicate and arrested two journalists. On Saturday an Egyptian court recommended the death penalty for three journalists charged with endangering national security.

"Legal action is a critical tool in the campaign against ISIL (Islamic State) but it must not be wielded like a cudgel against those who voice unpopular speech or criticise authorities," Power said.

"Such behaviour doesn't prevent violent extremism, it fuels it," she said.

While she did not name Egypt, Power directed her comments at Egyptian Foreign Minister Sameh Shoukry, who chaired the Security Council meeting on countering terrorism because Egypt is president of the group for May.

Shoukry said Power's comments were general and not directed towards Egypt, but that they had diluted the emphasis of the meeting. He met with Power privately on Tuesday.

"It is important that we keep a focus and that we send a clear message and do not confuse issues related to the battle against terrorism with other issues," he told reporters after Power's remarks. "We uphold the freedom of expression, we uphold the freedom of journalism."