WASHINGTON - The U.S. government has approved the sale to the government of the Philippines of two Sea Giraffe radars and related equipment, support and training for about $25 million, the U.S. Defense Security Cooperation Agency said on Wednesday.

The Philippines requested the sale to improve monitoring of its territorial waters. The radars will be installed on two Philippines Navy ships and the principle contractors will be VSE Corp and Saab.

The radar sale will allow the Philippines to beef up its maritime security and helps reinforce an important U.S. regional security relationship at a time when Washington is concerned about what it sees as China's overreaching claims in the South China Sea.

The Philippines has for decades been one of the closest U.S. allies in Asia, but the relationship has been strained recently as President Rodrigo Duterte has voiced disdain and mistrust of Washington while U.S. officials are worried over potential human rights violations under his government.

The U.S. Congress was informed of the radar sale and did not object.

A recent sale of assault rifles to the Philippines' national police was blocked in the U.S. Senate over concerns that they could be used against civilians.