North Korean leader Kim Jong-un inspected a local car industry complex and emphasized its role in efforts to foster the communist nation's economy, according to Pyongyang's state media Tuesday.

The report of Kim's visit to the Sungri Motor Complex came amid mounting pressure on the North from UN-led sanctions.

It also came hours after the Donald Trump administration put Pyongyang back on the list of state sponsors of terrorism, a move to impose further sanctions on the Kim Jong-un regime which the US president described as "murderous."

"The hostile forces' desperate efforts to block the advance of (North Korea) make the indomitable spirit of the Korean workers stronger and make them produce a great miracle startling the world," Kim was quoted as saying by the Korean Central News Agency.

He cited the newly produced 5-ton trucks at the complex in Dokchon, South Pyongan Province, the KCNA added in its English-language article. It is very important for the North to produce trucks by itself in order to develop its economy and strengthen its national power, Kim said.

Established in 1950, the factory is known for the assembly of the North's first truck, a 2.5-ton class vehicle named the Sungri-58. It has also developed a large production line for 40-ton cargo trucks.

As usual, the KCNA did not specify the date of Kim's activity, the first reported visit to an economy-related site in a week.

The North released a report last Wednesday on Kim's "field guidance" at the Kumsong Tractor Factory.

The North's official news agency and other state-controlled media kept mum on whether Kim met with Song Tao, a special Chinese envoy who made a four-day trip to the country. Song returned to Beijing on Monday.

Pyongyang has not formally responded yet to Washington's designation of it as a state sponsor of terrorism.

Trump said, "This designation will impose further sanctions and penalties on North Korea and related persons and supports our maximum pressure campaign to isolate the murderous regime."

He stressed that it should have been done so "a long time ago." The North was removed from the list in 2008 as part of the Bush administration's push for progress in denuclearization talks.

Many expect that the North won't sit idle. It is likely to respond with a strongly-worded statement or a provocative act.

"Currently, routine activities are being observed," Army Col. Roh Jae-cheon, spokesman for South Korea's Joint Chiefs of Staff, told reporters when asked about the North Korean military's move.

He added, "But we are maintaining a firm defense posture against various types of possible provocation."

The North has not carried out any provocative acts since its ballistic missile launch in mid-September.

The Chinese envoy's trip to Pyongyang raised hopes for a breakthrough in efforts to bring it back to the negotiating table. There has been no such news, however. (Yonhap)