White House: Cyberattack has not affected US government

President Donald Trump's homeland security adviser says that so far, no U.S. federal systems have been affected by the global cyberattack.

Tom Bossert says the U.S. government has been closely monitoring the attack, which has affected an estimated 300,000 machines in 150 countries. He said a few U.S. businesses, including Fed Ex, were affected.

Computers across the world were locked up Friday and users' files held for ransom when dozens of countries were hit in a cyber-extortion attack that targeted hospitals, companies and government agencies. Cybersecurity experts say the unknown hackers who launched the "ransomware" attacks used a hole in Microsoft software that was discovered by the National Security Agency and exposed when NSA documents were leaked online.

Neither the FBI or NSA would comment Monday.