White House counterterrorism chief John Brennan said on Wednesday that the intelligence community and law enforcement agencies are working to prevent any terror attack over the year-end holidays and are paying particular attention to rail and other transportation systems.

"As we enter the peak of another holiday season, the homeland security, law enforcement, and intelligence communities are collectively focused on doing everything they can to prevent terrorists from disrupting the safety and security of Americans as they travel, spend time with family and friends, and enjoy holiday festivities both at home and abroad," Brennan said at a White House briefing.

Some U.S. media reported on Tuesday that American intelligence officials were gearing up for the possibility of a Christmas terror attack from al-Qaeda.

Americans still remember the near-disaster bombing plot when a Nigerian man tried to blow up a U.S.-bound airliner on Christmas Day last year.

Brennan said the United States has taken steps to ensure past anti-terror failures are not repeated.

Senior officials from departments and agencies met on Tuesday at the White House to review the latest threat reporting and to coordinate security and counterterrorism plans that will be in place during the holiday season, he said.

Brennan also noted that the United States is working closely with other governments to share threat information and to coordinate counterterrorism and security activities.

"These international partnerships are critically important to our ability to identify would-be terrorists and to thwart their plans before they are able to act," he said.