The United States' Homeland Security Department is planning to station American inspectors in foreign airports to screen passengers, the Wall Street Journal reported on Monday.
Citing US Customs chief Robert Bonner, the story said the initiative, which is still being developed, would aim to identify and catch possible terrorists before they board a US-bound plane.
US customs is considering seven specific cites but has yet to seek support from host countries, the story quoted Bonner as saying. International hub airports such as London's Heathrow and Narita in Japan could come under the plan, the story said.
"It will be voluntary," said Bonner. "Nobody has to participate in these things unless they find it in their interests to provide better security," he told the newspaper.
This could help avoid the kind of flight cancellations sparked by terrorist fears that were ordered over the holidays in late December, the paper said, quoting Bonner.
The plan could save carriers $10,000 fines that are payable when they bring someone in who is blocked by US immigration, the story said.