The Japanese and U.S. governments have begun to avoid using the negative term "burden" in official documents when referring to the vast tracts of land occupied by U.S. military bases and facilities on the island of Okinawa.

Instead of "burden," which appears repeatedly in the bilateral agreements of the past decade, they are starting to state the need to reduce the "impact" on Okinawa residents.

Chief Cabinet Secretary Yukio Edano said Monday that the term was changed after repeated talks with the United States.

"The government's understanding that Okinawa has had to shoulder a heavy burden because of the high concentration of U.S. military bases in Okinawa has not changed," Edano stressed. But "there have been various discussions on whether or not the term 'burden' was appropriate between the Japanese and U.S. governments, which resulted in the expression to "reduce the impact.' "

In a statement signed last week by the foreign and defense ministers of Japan and the U.S., both sides "reaffirmed the commitment to reducing the impact on local communities, including in Okinawa, in turn helping to ensure a sustainable U.S. military presence in Japan."

This is the first time "burden" has completely disappeared from bilateral documents.

"There is a big difference between burden and impact," said Okinawa Gov. Hirokazu Nakaima, who was visiting Tokyo Monday, where he met with Prime Minister Naoto Kan and other key officials. The governor said he was later going to meet with Foreign Ministry officials and ask them for further details on the change.