President Donald Trump signed an executive order on Tuesday ordering federal agencies to strengthen the resiliency of critical American infrastructure against electromagnetic-pulse attacks.

The order is the "first ever to establish a comprehensive policy to improve resilience to EMPs," White House press secretary Sarah Huckabee Sanders said.

The EMP threat has been a hotly debated point, with some arguing it is an existential threat, while others believe it to be a conspiracy theory.

President Donald Trump signed an executive order on Tuesday to protect the US from electromagnetic pulses (EMPs) that could have a "debilitating" effect on critical US infrastructure.

Trump instructed federal agencies to identify EMP threats to vital US systems and determine ways to guard against them, Bloomberg first reported. A potentially harmful EMP event can be caused by a natural occurrence or the detonation of a nuclear weapon in the atmosphere.

The threat of an EMP attack against the US reportedly drove the president to issue Tuesday's order. Multiple federal agencies, as well as the White House National Security Council, have been instructed to make this a priority.

"Today’s executive order — the first ever to establish a comprehensive policy to improve resilience to EMPs — is one more example of how the administration is keeping its promise to always be vigilant against present dangers and future threats," White House press secretary Sarah Huckabee Sanders said in a statement, according to The Hill.

With the release of the White House National Security Strategy in 2017, Trump became the first president to highlight the need to protect to the US electrical grid.

"Critical infrastructure keeps our food fresh, our houses warm, our trade flowing, and our citizens productive and safe," the document said.

"The vulnerability of U.S. critical infrastructure to cyber, physical, and electromagnetic attacks means that adversaries could disrupt military command and control, banking and financial operations, the electrical grid, and means of communication."

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Senior US officials warned that the US needs to take steps to safeguard the electrical grid and other important infrastructure against EMP attacks, The Washington Free Beacon reported on Tuesday. "We need to reduce the uncertainty in this space" and "mitigate potential impact" of an EMP attack, one senior administration official said.

"We are taking concrete steps to address this threat," the official added. "The steps that we are taking are designed to protect key systems, networks and assets that are most at risk from EMP events." Federal agencies are being tasked with bolstering the resiliency of critical infrastructure.

Members and supporters of the decommissioned US Commission to Assess the Threat to the United States from Electromagnetic Pulse have long warned of the possibility of an EMP attack, with some individuals, such as Peter Pry, who previously led the congressional EMP commission, asserting that an EMP attack on America could kill off 90% of the US population.

Those seeking to raise awareness have pointed to the threat from solar flares, as well as nuclear-armed adversarial powers.

Others, including Jeffrey Lewis, a renowned nuclear-weapons expert, have said that the EMP threat is a conspiracy. Lewis previously wrote that it seemed "like the sort of overcomplicated plot dreamed up by a Bond villain, one that only works in the movies. Bad movies."