MANILA - President Rodrigo Duterte on Monday said warmer relations between Manila and Beijing have improved the negotiating environment for the unresolved South China Sea dispute.

"We have cultivated warmer relations with China through bilateral dialogues and other mechanisms, leading to easing of tensions between the two countries and [an] improved negotiating environment on the West Philippine Sea," he said in his second State of the Nation Address.

The West Philippine Sea is the Philippines' exclusive economic zone within the disputed South China Sea.

Ties between the Philippine and China had soured after Manila initiated an arbitration case against Beijing for overlapping claims in territories in the South China Sea.

The Philippines won the case, with the arbitral tribunal deciding in July 2016 that China's nine-dash line claim over nearly all of the South China Sea was invalid. China has ignored the ruling and instead ramped up militarization and island-building activities in the disputed waters.

Still, Duterte has pursued improved economic and defense ties with China, shelving the Philippines' arbitral victory while turning away from the country's long-standing alliance with the United States.

But he vowed to raise the matter if China begins exploiting resources in the disputed waters.

• READ: Duterte to raise arbitration win if China exploits disputed waters

Duterte, who flew to Beijing twice in his first year in office, said his administration is pursuing an independent foreign policy and that the people and interests of the country would take precedence in resolving international disputes.

• READ: PH says S. China Sea row should be resolved in 'neighborly' manner

In his speech, Duterte said the Philippines took on various initiatives to "advance our national interests in the global community," as it pursued "good relations with all nations, anchored on an independent foreign policy and the basic tenets of sovereign equality, mutual respect, and non-interference."

Southeast Asian nations, he added, "will uphold and promote our national interests in the international community," as the Philippines hosts the summit of leaders later this year.

"We will strengthen and seek partnership with those who share our values. We will engage nations with full respect for the rule of law, sovereign equality, and non-interference," he said.

He once again pounced on critics from the west, lashing out at criticism on his war on drugs.

• READ: In 2nd SONA, Duterte reiterates 'unrelenting' campaign vs drugs