LONDON, England (AP) -- Islamist militants want to attack the Channel Tunnel between England and France during the holiday season, a British newspaper reported Sunday, citing French and U.S. security sources.

The Observer said the French foreign intelligence service, DGSE, warned the French government of the threat in a Dec. 19 report after a tip-off from the CIA. The newspaper cited French sources as saying the plot was being directed from Pakistan and involved Western European militants, possibly Britons of Pakistani descent.

The newspaper said U.S. sources described the threat to the tunnel, which is used by millions of rail passengers each year, as "sky high."

French Defense Ministry officials had no immediate reaction to the report.

The newspaper also claimed that al Qaeda-linked militants were plotting a wave of attacks on an unidentified European country, with the plot planned and run from Syria and Iraq. It said the threat was greatest between September 2006 and April 2007.

British officials have warned there is a high threat of an attempted terrorist attack over the Christmas and New Year period, although they say they have no specific intelligence of any plots.

Metropolitan Police Commissioner Ian Blair said Friday that "the threat of another terrorist attempt is ever present."

"Christmas is a period when that might happen," he said, but added, "We have no specific intelligence to do (with) that."