John Bolton has been called in to testify in the impeachment inquiry into US President Donald Trump.
The former National Security Adviser has been summoned by the House of Representatives investigators.
The US President is being investigated for pressuring Ukraine to investigate former US Vice-President Joe Biden and his son.
Trump denies the claims.
Bolton, who has spoken against the president on the matter, has been asked to testify on November 7.
Rescuers comb Venezuelan quake rubble, thousands reported missing
Rescuers worked through the night on Friday to save hundreds of Venezuelans trapped in rubble and find thousands more missing after two of the biggest earthquakes in Latin America's modern history smashed areas in and around the capital Caracas.
Traffic through Strait of Hormuz slows after attack on ship
Fewer vessels transited the Strait of Hormuz on Friday than earlier this week, hours after a Taiwanese-operated ship was fired on by Iran, ship tracking data showed.
Europe on high alert as killer heat spreads
Health authorities across Europe were on high alert on Friday as a killer heatwave progressed across the continent.
Japan braces for double storms, torrential rains shut down parts of Taiwan
Japan grappled with transport disruptions on Friday while bracing for more torrential rain and risks from two approaching tropical storms that spurred authorities to issue high-level landslide warnings and order the evacuation of 1 million people.
Australia pledges tougher enforcement of social media ban for teens
Australia's prime minister vowed on Friday to bullet-proof laws supporting a social media ban for under-16s as the government prepares legal action against platforms amid a steady stream of evidence that the ban has had little impact on teen use.
