The US is warning the Philippines to think very carefully about its plan to purchase military equipment from Russia, including diesel-electric submarines, and stressing that Russia is an unsavory partner.

The Philippines, a US ally in East Asia, is interested in acquiring its first batch of submarines to strengthen the navy amid tensions with China in the South China Sea.

Philippine Defense Secretary Delfin Lorenzana said in June that his country needs submarines to keep up with neighboring states.

“We are the only ones that do not have [undersea capabilities],” Lorenzana explained at a flag raising ceremony, the Manila Times reported. “We are looking at [South] Korea and Russia and other countries …