A new United States government report warns US relations with Micronesian countries are being threatened by China's inroads in the Pacific region.
The report by the US-China Economic and Security Review Commission was released last week.
The report warns Chinese investments in casino resorts on the Northern Marianas' island of Tinian could complicate US military plans for the island.
It says rapid growth in Chinese investment and an influx of Chinese tourists in the Marianas is fueling local opposition to the plans.
The report for the US Congress quotes a retired Pacific commander warning China is trying to control US access to the Marianas and Guam through what he termed "suspect casino operations" and energetic law enforcement was needed.
The report also urges beefed up US investment in all of its territories and the compact countries in Micronesia where long term American presence is not guaranteed.
It highlighted concern that China is seeking to open up access for its military in the Pacific by eroding US regional influence.