The sources said the deliberations in Washington and Taipei's separate lobbying of EU envoys were both at an early stage - a response to fears of a Chinese invasion that have grown as military tensions escalate in the Taiwan Strait.
The idea is to restrict some trade and investment with China in sensitive technologies like computer chips and telecoms.
Reuters was unable to learn details on what specific sanctions were under consideration, but some analysts suggested China's military could be the focus. Responding to the news on the sanctions package, a foreign ministry spokesperson in Beijing warned against underestimating China.
The White House declined to comment.