Diplomats from 20 countries agreed to consider fresh sanctions against North Korea at a US-Canadian summit in Vancouver on Tuesday.

Any new sanctions would be unilateral and go beyond United Nations sanctions passed in response to Pyongyang's recent nuclear weapons and ballistic missile tests, according to a joint statement.

The US-Canadian sponsored summit was announced after Pyongyang tested its most advanced ballistic missile in November. Representatives of the countries that were involved in backing South Korea during the 1950-1953 Korean War were in attendance.

Read more: North Korea slams latest UN sanctions as 'act of war'

During the meeting, the United States also told allies to bolster the US-led "maximum pressure" campaign against North Korea by stopping any attempts to evade existing sanctions against the pariah country.

"We must increase the costs of the regime's behavior to the point that North Korea must come to the table for credible negotiations," US Secretary of State Rex Tillerson told senior diplomats in the western Canadian city. "We will not allow North Korea to drive a wedge through our resolve or solidarity."

Read more: Kim Jong Un: North Korea has completed nuclear program, US will never attack

Shared skepticism

Many officials argued the international community needed to maintain its economic pressure against Pyongyang despite its recent diplomatic overture to South Korea.

"It is not the time to ease pressure or to reward North Korea," Japanese Foreign Minister Taro Kono said. "The fact that North Korea is engaging in dialogue could be interpreted as proof that the sanctions are working."

The world, he added, should be wary of the North's efforts to talk with the South, which he described as a "charm offensive."

Read more: Do Korea talks put initiative back with Seoul and Pyongyang?

Pyongyang and Seoul held face-to-face talks in early January for the first time in two years, with both sides agreeing to Pyongyang's participation at the Winter Olympics in the South Korean city of Pyeongchang in February. More talks were held Wednesday in the border village of Panmunjom and officials reportedly agreed that the North would send a 230-member cheer section to the Games.

South Korean Foreign Minister Kang Kyung-wha acknowledged the North had not yet signaled a willingness to roll back its nuclear weapons program, but said bilateral talks had been a "significant first step toward restoring inter-Korean relations."

Read more: North Korea to send its national orchestra to South for Winter Olympics

China, Russia critical

China and Russia, which fought alongside the North in the Korean War and were not invited to Vancouver, criticized the meeting.

Russian Foreign Minister Sergey Lavrov said the meeting was "unacceptable" and "destructive," according to Tass news agency.

A spokesman for China's Foreign Ministry, Lu Kang, said the meeting could not lead to any solutions to the Korea tensions because "important parties" did not attend.

Despite their absence, Tillerson called on Moscow and Beijing to fully implement UN sanctions against Pyongyang that both have supported.

US President Donald Trump accused China in December of transporting oil to North Korea. Western security sources told Reuters news agency reported that same month that Russian ships had transferred oil to North Korean vessels.

Tillerson also rejected a Chinese-Russian proposal for the North to halt its nuclear weapons and missile programs in exchange for the US and South Korea ending their joint military exercises on the Korean peninsula.

Read more: Russia's Sergei Lavrov slams US for ignoring 'multipolar' world

amp/sms (Reuters, AP)