Several of the world’s most powerful democracies are urging governments and companies to start preparing their systems for a future in which quantum computers could break widely-used forms of encryption.

In a joint advisory released Thursday, the G7 Cyber Security Working Group and the U.S. Cybersecurity and Infrastructure Security Agency, CISA, said organizations should begin moving to post-quantum cryptography now, rather than waiting until sufficiently powerful quantum computers become available.

“Although the exact timeline is uncertain, several recent advances suggest an anticipation of the development of quantum computers,” the advisory said.

Post-quantum cryptography is a type of encryption designed to protect data from attacks by both traditional and quantum computers. According to the G7 and CISA, organizations may already be exposed to the threat.

Hackers can steal encrypted information and store it in the hope of decrypting it once more powerful quantum computers become available, an approach commonly known as “harvest now, decrypt later.” The threat is particularly relevant for information that needs to remain secret for many years, including government records, sensitive personal information and corporate trade secrets.

“This means that organizations may already be exposed to the threat today,” the advisory said.