WASHINGTON (AP) — President Donald Trump has signed an executive order aimed at modernizing and improving the nation's computer networks.

Trump's homeland security adviser Tom Bossert says the order will help keep the U.S. safer from cybersecurity risks. Among the new requirements is that agency heads must be accountable for implementing risk management measures.

Trump pledged in late January to strengthen the government's ability to protect its computer networks, but then canceled plans to sign an executive order on cybersecurity without explanation.

The order comes while Trump is under intense scrutiny over his decision to fire former FBI Director James Comey, who was leading an investigation into alleged Russian hacking in last year's election and possible ties to Trump associates.