The Indonesian legislature has approved a nearly ten-percent increase in the nation’s defense budget following a visit by President Joko Widodo to Natuna Island, a territory on the cusp of China’s “nine-dash line,” unilaterally defining Beijing’s borders as extending into five other countries.

Reuters reports that the legislature passed a new budget allotting for $8.25 billion to be spent on defense in 2016, specifically citing China’s growing presence in the South China Sea as the issue making the new defense spending necessary. Lawmakers had already increased defense spending to $8.076 billion last Thursday, during which President Widodo was conducting a personal trip to Natuna.

“(Natuna) needs to be guarded and to do that the military needs to have proper facilities, they need additional funds,” Reuters quotes Indonesian Parliament member Johnny Plate as stating. While no Indonesian land falls within the nine-dash lines, the waters around Natuna Island do, and the Chinese government has expanded its presence in those waters. According to the UN Convention on the Law of the Sea (UNCLOS), the waters surrounding the territory of a sovereign nation also belong to that nation within 12 nautical miles.

During his trip, Widodo emphasized the need to protect Natuna and its waters for foreign occupation. Widodo held a cabinet meeting on a warship stationed in Natuna, in which he called for increased military capability in the region. “I ask the military and Bakamla to upgrade their capabilities to safeguard our territorial waters in terms of technology, equipment, radar and preparedness,” Jokowi said in a statement.

Holding a cabinet meeting there “sends a clear message” that the nation is “very serious in its efforts to protect its sovereignty,” Political, Legal and Security Affairs Minister Luhut Pandjaitan told the Jakarta Times following the announcement of the meeting. Luhut appeared intent to ensure observers understood the meeting, and the visit to Natuna, was about China.

“In the course of our history, we’ve never been this stern [with China]. This is also to demonstrate that the President is not taking the issue lightly,” he added.

Chinese fishermen have become increasingly present in Natuna waters. Most recently, China leveled a complaint at Indonesia for arresting a ship full of Chinese fishermen illegally present in Indonesia’s waters. Foreign Ministry spokeswoman Hua Chunying alleged that one of the anglers arrested was injured and asserted, “China strongly protests and condemns such excessive use of force.” Hua reiterated China’s claim that Natuna’s waters are a “traditional Chinese fishing ground,” though that claim was once again not elaborated on.

“Whatever the flag, when they commit violations inside Indonesia’s jurisdiction, we, in this case the navy, will not hesitate to act decisively,” Indonesian Navy spokesman Edi Sucipto said in response to the protest.

A similar event occurred in March, where Indonesian authorities seized a Chinese ship illegally exploiting its waters, and China used the same language to deny Indonesia’s sovereignty in Natuna waters: they are a “traditional Chinese fishing ground.” China does not claim the island itself, only its surrounding waters.

The land China claims in the region overlaps with the sovereign territory of Taiwan, Brunei, Vietnam, Malaysia, and the Philippines. The Philippines has sued China in the Permanent Court of Arbitration at The Hague; a verdict is expected this summer.