North Korea's trade with China is showing signs of revival despite Beijing's pledge to strictly implement sanctions against the reclusive country for its nuclear test and long-range missile launch early this year, a source said Sunday.

The claims come as China has raised objections to the deployment of an advanced U.S. missile shield in South Korea and may be an indication that Beijing is backtracking on its sanctions obligations.

Seoul and Washington announced on July 8 that a Terminal High Altitude Area Defense battery will be deployed on the Korean Peninsula. The allies claimed that the system is defensive and is only aimed at countering the North's threat, but China has argued the deployment undermines its national security interest.

Lim Eul-chul, research professor at Kyungnam University's Graduate School of North Korean Studies said that his contacts in China have hinted that while Chinese customs offices ostensibly claim they are adhering to the United Nations Security Council resolution restricting transactions with Pyongyang, there has been a noticeable easing in oversight by authorities.

"Chinese companies who had held back on trading with the North, have started to ship more goods after hearing the news that Seoul-Beijing relations have taken a turn for the worse over the THAAD issue," the scholar said.

He also said that there have been reports of greater traffic moving between the country at night and early morning hours. Lim said that taking into account the customs office operating hours, the flow of traffic at such hours could indicate the illegal movement of goods.

This view was echoed by Cho Bong-hyun, an analyst at the IBK Economic Research Institute, who said that people living in the Sino-North Korean border region are saying customs inspections have become lax along the Sino-North Korean border.

"There is even speculation that banned items are being disguised as products that are not subject to the UNSC sanctions and are being traded," he said.

Reflecting this, two-way trade data between the neighboring countries support this.

Official customs data released by China showed bilateral trade hitting $503.77 million in June, up 9.4 percent on-year, and the first rebound just three months after Beijing said it will clamp down on trade. The increase is significant because it took place before the THAAD deployment was announced.

According to U.S.-based Radio Free Asia, people in Liaoning Province said that the number of cargo trucks coming out of North Korea on a daily basis has jumped twofold to 20 from just 10 two months earlier.

"While trucks only arrived twice a week from North Korea to China just a few weeks ago, they are currently arriving every day, which may be neutralizing the international sanctions," the media outlet citing a source said. The local said that the traffic involved container trucks.

The RFA then said the popularity of daytrips to North Korea's border city of Sinuiju by Chinese nationals is a testament to the erosion of Beijing's resolve to clamp down on trade with the North. (Yonhap)