BRUSSELS, February 13. /TASS/. The unidentified balloons above the US is a sign of Russia and China ramping up their intelligence activities against NATO countries, NATO Secretary General Jens Stoltenberg said during a press conference in Brussels Monday.

"What we saw over the United States is part of a pattern where China and also Russia are increasing surveillance activities on NATO allies," Stoltenberg said.

According to the Secretary General, NATO sees that in different areas.

"We see it in cyber, we it with satellites, and we see it with balloons. That highlights the importance of our vigilance, our increased presence," the official said.

Stoltenberg underscored that this issue confirms the need for NATO’s tighter control over its air space. To that extent, the alliance plans to create a new virtual network that will combine information from both civilian and military satellites for reconnaissance purposes.

Earlier, US authorities have detected a Chinese balloon at an altitude that significantly exceeded that of commercial flights. On February 4, US Air Force downed this "surveillance balloon" inside the US airspace. According to the Pentagon, the balloon was gathering important information. Due to this incident, US Secretary of State Antony Blinken postponed his visit to China, while the Chinese Foreign Ministry expressed its protest against US outbursts and libel. Beijing explained that the Chinese meteorological probe ended up in the US airspace by accident.