Gas prices will increase next month, with unleaded grades going up by about 4 cents a gallon and diesel, three times that amount, the Army and Air Force Exchange Service announced late Monday.

The rise in fuel prices will affect AAFES customers in Germany, Netherlands, United Kingdom, Turkey and the Azores beginning on Friday, according to an AAFES news release.

AAFES based the increase on the rise in the average price for all grades of fuel in the United States, as cited by the Department of Energy. The period covers a four-week stretch that ended Aug. 22.

By grade, the average increase per gallon will be regular – 3.8 cents; mid-grade – 4 cents; premium – 4.7 cents; and diesel – 12.2 cents.

In Germany, unleaded will cost $3.157 per gallon; super unleaded, $3.260; super plus unleaded, $3.366; and diesel, $3.199.

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