Tillerson doubles down as China takes new hard line on North Korea The secretary of state is meeting with Asian leaders in Manila Sunday.

MANILA, Philippines -- Secretary of State Rex Tillerson is on the offense at a summit here as he tries to increase the pressure on, and isolation of, North Korea after the U.N. Security Council imposed new sanctions against the country's rogue regime.

Tillerson is in Manila for an annual summit hosted by Southeast Asian countries collectively known as ASEAN. He’s meeting with regional partners, including Russia and China, just days after North Korea tested its second intercontinental ballistic missile in a month.

The new sanctions were drafted by the U.S. in consultation with China and passed unanimously at the U.N. Saturday. They block North Korean sales of coal, iron and iron ore, lead and lead ore, and seafood. The sanctions also halt any expansion of North Korea’s guest worker programs in other countries.

The revenue from these different sectors, worth as much as $1 trillion annually by U.S. estimates, is believed to fund North Korea’s expensive ballistic missile and nuclear programs. North Korea earns approximately $3 billion per year from exports, according to the U.S. mission to the U.N., meaning the sanctions could block as much as one-third of North Korea’s revenue.

The resolution also prohibits any new joint business ventures with North Koreans and limits existing ones and blacklists 13 new North Korean individuals and entities, including its primary foreign exchange bank.

“It was a good outcome,” Tillerson told reporters ahead of his meeting with South Korean foreign minister Kang Kyung-wha. A senior aide to Tillerson told ABC News that China signing off on anything is a major accomplishment.

But it remains to be seen how strongly China, North Korea’s largest trading partner, will implement the new sanctions.

“It’s certainly a good step that they’ve moved ahead to broaden the sanctions,” Acting Assistant Secretary of State for East Asia and Pacific Susan Thornton told reporters Sunday, “but the implementation is something that we’ll be tracking and taking action on as necessary,” including possible unilateral U.S. sanctions on Chinese banks, firms, and individuals.

For its part, China took a stronger line on its neighbor publicly, with Chinese Foreign Minister Wang Yi warning, “Do not violate the U.N.’s decision or provoke the international society’s goodwill by conducting missile launches or nuclear test.”

China urged restraint from the U.S. and South Korea as well though, calling on all sides to negotiate.

“Sanction is necessary, but sanction is not the ultimate purpose," Wang told reporters. "Our purpose is to bring all parties involved in the nuclear issues back to negotiation table."

China has suggested the U.S. and South Korea halt joint military exercises in exchange for a halt to North Korea’s nuclear and ballistic missile testing. Thornton reiterated Sunday that the U.S. rejects such a “freeze-for-freeze,” calling it a false moral equivalency.

But the Trump administration has said it is open to negotiations once North Korea halts its illegal ballistic missile and nuclear programs. “This pressure campaign, the sanctions -– it’s all about trying to convince the North Koreans that the best way forward is for them to come back to the table and talk,” Thornton added.

In the meantime, the push to isolate North Korea continues, including here in Manila. The U.S. is still pushing for North Korea’s expulsion from the ASEAN Regional Forum, a 27-member body that deals with security issues, and some members have been receptive to the idea, according to Thornton.

Still, the Chinese delegation held a one-on-one meeting with North Korea, noting it was “normal” because “North Korea is China’s neighbor.”

Back in the U.S., President Trump also celebrated the new sanctions with several tweets and a statement from his press secretary Sarah Sanders late Saturday night.

Days after blaming China for doing “NOTHING for us with North Korea, just talk,” the White House made special mention to note, “The President appreciates China’s and Russia’s cooperation in securing passage of this resolution.” Trump added in a presidential tweet Saturday that the sanctions will have a “Very big financial impact!”