Chinese state media are reporting that a massive deepwater oil platform, Marine Oil 981, will begin testing this week for the first time in preparation for its deployment to the South China Sea in July.

The deployment of the semi-submersible platform comes as tensions rise in the hotly contested South China Sea. Shortly after China announced the completion of the platform — which took more than three years to build and cost more than $900 million — Philippine officials voiced concern and asked China where it was sending the oil platform.

Chinese state media say the oil rig is 114 meters long, 140 meters high and weighs 31,000 tons. According to China State Shipbuilding Company, the deepwater platform is capable of drilling in waters up to 3,000 meters deep, and of using a drill that goes as deep as 12,000 meters.

Chinese energy officials say the oil rig is strategically significant and will help China boost its deepwater oil drilling capability. Engineers tell Chinese state media that the rig is specially designed to operate in the rough waters of the South China Sea.