Zbigniew Brzezinski, a hawkish Polish-American diplomat who served as National Security Adviser to former US President Jimmy Carter in the late 1970s, died at the age of 89 on Friday. His daughter, Mika Brzezinski, announced his death on her personal social media account.

"My father passed away peacefully tonight. He was known to his friends as Zbig, to his grandchildren as Chief and to his wife as the enduring love of her life," read the post.

Brzezinski died at Inova Fairfax Hospital in Falls Church in Virginia, according to The New York Times. The cause of his death has not been released.

In the years working with Carter, he helped deal with several international issues including a failed rescue mission during the 1979 Iranian hostage crisis.

Zbigniew Brzezinski in his office at the White House in March 1977. /VCG Photo 

Key figure in China-US relations

As National Security Adviser for the Carter administration from 1977 to 1981, Brzezinski played an essential role in pushing forward the normalization of China-US relations.

He visited Beijing in May 1978, a journey which set a good foundation for the establishment of diplomatic relations between China and the US. Months later in December, the two countries formally established a diplomatic relationship.

During his visit, Brzezinski told Beijing that then President Carter was willing to normalize relations with China before his first term ended and the US would accept three principles put forward by China for the establishment of diplomatic ties – the US must sever its diplomatic relations with Taiwan, abrogation of the mutual defense treaty between the US and Taiwan, and the withdrawal of all US forces from Taiwan. 

Here is CGTN's interview with Zbigniew Brzezinski in 2014: