GENEVA: U.N. war crimes investigators called Monday on European countries to let them interview more newly-arrived Syrian refugees to document fresh violations, saying it had become increasingly difficult.

"We are appealing to countries inside Europe hosting newly arrived Syrian refugees to grant us access and remove any barriers to our work," Paulo Pinheiro, chairman of the U.N. Commission of Inquiry on Syria, told the U.N. Human Rights Council in Geneva.

"Time is of the essence, particularly if the Commission is to continue preparing well-documented reports on the current situation in the country, rather than reports of a historical nature," he said.

The independent panel, set up five years ago, says it has compiled a confidential list of suspects on all sides of the conflict that have carried out war crimes or crimes against humanity.