MOSCOW, January 9. /TASS/. Ukrainian President Vladimir Zelensky has declared January 9 a day of mourning after a Ukrainian plane crashed in Iran, the president’s office said in a statement after a working meeting on Thursday.

"In order to pay tribute to those killed the president ordered to lower Ukrainian national flags at half-mast at houses and buildings of Ukraine’s state authorities, local government, state enterprises, agencies and organizations," the statement reads.

On January 8, Ukraine International Airlines Boeing 737 went down in the Iranian capital of Tehran shortly after takeoff from the Imam Khomeini International Airport. All 176 people onboard died in the crash.

Ukrainian Foreign Minister Vadim Pristaiko announced on his Twitter page that citizens of Iran, Canada, Ukraine, Sweden, Afghanistan, Germany and the UK were among those killed.