What happened? 
The United States sent three naval ships to patrol near oil and gas operations off the coast of Malaysia. Over the last few weeks, the US Navy and Air Force B-1 bombers have been active in the South China Sea. Consequently, around 14 May the satellite image illustrates that China has deployed early warning aircraft and anti-submarine aircraft on the Yongshu Reef in the region.

What is the background? 
First, the US support to Malaysia. Two ships, the Independent -variant littoral combat ship USS Montgomery and the Lewis and Clark-class dry cargo ship USNS Cesar Chavez conducted "presence operations" near West Capella (under Malaysian oil and gas company). The commander of the US Pacific Fleet has reiterated that the US is committed to maintaining "a rule-based order" in the South China Sea. 

Notably, it is not the first time that the US Navy has conducted Freedom of Navigation Operation (FONOP) adjacent to the West Capella. It was a reaction to the "harassment", the Chinese had caused to the drillship in the international waters. The PLA-N had expelled the guided-missile destroyer, USS Barry, from the Paracel Islands in the South China Sea on the pretext that the US was intruding into the Chinese waters. 

Second, China's unilateral actions during the pandemic. It set up two new administrative structure under the local government in Sansha, Hainan Province. (In 2012, Sansha was included as a prefecture-level city in the Hainan province.) On the pretext of conserving rock, from 1 May, China has prohibited fishing activities in 12th parallel including regions near the Scarborough Shoal, the Paracel Islands, and the Gulf of Tonkin. 

What does it mean? 
First, China claims 80 per cent of the South China Sea and has declared it a 'core issue'. Over the past six years, China is building artificial islands and facilities in the disputed area. This has become a source of conflict between the major claimants.  Second, the South China Sea has become a major irritant in the ongoing US-China trade dispute. 

In these developments, China is using its military to send a message that it is capable of operating even at a longer distance for a longer period to challenge the other claimants and the US. On the other hand, the US is increasing its presence in the South China Sea and accusing China of taking leverage of the COVID-19 to increase its sphere of influence in the region. 

The US forces have not confronted the Chinese directly in the South China Sea region. Yet, the US navy conducts FONOP frequently in the region. The transit of USS Montgomery signifies that the US is ready to deploy the two variants of the Littoral Combat Ship (LCS) class on a high-profile mission. Both the LCS series was suspended in 2016 due to operational difficulties. The US is in the process of helping Malaysia build its maritime domain awareness capabilities by providing 12 Scan Eagle UAS systems and converting three Royal Malaysian Air Force CN-235 transport aircraft into maritime surveillance aircraft.