A US think tank says satellite images show that while North Korea may have temporarily canceled plans for a spy satellite launch, preparations are underway to proceed with it in the near future.

The Center for Strategic and International Studies, or CSIS, released on Tuesday the results of an analysis of imagery captured early this month of the Sohae satellite-launching station.

The facility is located in Tongchang-ri in the country's northwest.

CSIS researchers say imagery taken on April 8 shows 10 vehicles in the courtyard of the administration and security headquarters. They note, "Such a concentration of vehicles has historically coincided with past test launches."

However, they say these vehicles were gone by April 10, suggesting "that a satellite launch was planned but was canceled for unknown reasons."

The researchers also say an April 8 image shows the presence of three vehicles at a VIP facility that is frequented by leader Kim Jong Un for observing launches. But they say only one vehicle remained by April 10.

They add, "The lingering presence of this vehicle implies that while the launch has been postponed, preparations continue for an anticipated launch in the near future."

North Korea says it put its first military reconnaissance satellite into orbit last November. The country plans to launch three more spy satellites in 2024.

South Korea's Defense Minister pointed out on Sunday that although Pyongyang's preparations for the launch have fallen behind schedule, it could be carried out by the end of April at the latest.