© Wall Street
US President Donald Trump has signed off on a new cyber strategy - the first such document in 15 years - outlining defensive priorities and threatening offensive action against foreign hackers.

"Today the president signed a national cyber strategy, the first fully articulated cyber strategy in 15 years," National Security Adviser John Bolton told reporters on Thursday. "The strategy takes effect today."

The 35-page document, made public by the White House, is the first time the US has articulated an offensive cyber strategy. It rolls back many of the restrictions placed on Washington's digital warriors under Trump's predecessor, according to Bolton.

"Our hands are not tied, as they were in the Obama administration," Bolton said. "Our presidential directive effectively reversed those restraints, enabling offensive cyber operations through the relevant departments."

Any country that takes cyber activity against the US can expect Washington to "respond offensively as well as defensively," Bolton added. "Beyond that, I'm just not going to go at this point."

The primary goal of the strategy, according to Bolton, is to secure critical government and infrastructure systems, improve incident reporting, and fight cyber crime. There will also be a focus on attributing cyber attacks, in order to create "norms of responsible state behavior." The strategy also seeks to promote open, reliable and interoperable internet worldwide, Bolton said.

Among the listed goals was also the development of a "superior cybersecurity workforce" and promotion of US innovation in cybersecurity.