By Tamiyuki Kihara TOKYO (Reuters) -Japan and the United States are in the final stages of talks to implement lower tariffs on Japanese automobile imports within 10-14 days after the issuance of a U.S. presidential executive order, a Japanese government source told Reuters on Thursday. That means a reduced tariff rate on Japanese cars, from the current 27.5% to 15%, is set to take effect by the end of this month, said the source, who declined to be identified as the matter is private. The exact date to be specified in the executive order is still under discussion, the source said, adding that the final decision would ultimately rest with U.S. President Donald Trump. The U.S. embassy in Tokyo did not immediately respond to a request for comment. (Reporting by Tamiyuki Kihara; Writing by Makiko YamazakiEditing by Gareth Jones)