WASHINGTON (REUTERS) - US President Donald Trump on Thursday (May 11) signed an executive order to bolster the government's cyber security and protect the nation's critical infrastructure from cyber attacks, the White House said, marking his first significant action to address what he has called a top priority.

The order seeks to improve the network security of US government agencies, from which hackers have pilfered millions of personal records and other forms of sensitive data in recent years.

It also aims to better protect critical infrastructure, such as the energy grid and financial sector, from sophisticated attacks that officials have long warned could pose a national security threat or cripple parts of the economy.

The order additionally lays out goals to develop a more cogent cyber deterrence strategy, in part by forging strong cooperation with US allies in cyberspace.

White House Homeland Security Adviser Tom Bossert said the order sought to build on efforts undertaken by the Obama administration.

"A lot of progress was made in the last administration, but not nearly enough," Bossert told reporters during a White House briefing.

Trump nearly signed a cyber security measure just days into his presidency in January, but it was pulled back to allow for more input from different federal agencies and consultation with experts.

The presidential campaign featured running storylines related to cyber security, including the hacking and subsequent leaking of Democratic emails as part of what US intelligence agencies determined was a wide-ranging operation carried out by Russia to help Trump win the White House and denigrate his challenger, Democrat Hillary Clinton.

Russia has repeatedly denied assertions it has user cyber means to meddle in the US election.

Bossert said Russia's alleged election hacks were not a motivation for the order.

"The Russians are not our only adversary on the Internet," Bossert said.