Central Intelligence Agency (CIA) director William Burns has said that China is the biggest geopolitical challenge to the US in the 21st century.

Highlighting the rise of China, Burns said in a wide-ranging interview on Thursday with NPR that the US intelligence service might now have to forward-deploy its 'China specialists' to compete effectively with Beijing.

The agency's director also added that the technology sector was the biggest area of competition between the two countries.

Quoting to Burns as saying in the NPR interview, report says, '...I am exploring right now, to forward-deploy China specialists - whether it is operations officers, analysts, technologists as well - to make us more effective in that competition, in that rivalry in the field as well.

Talking about troop rollout in Afghanistan,  Director Burns also said that the US still retains 'significant capabilities' in and around Afghanistan to gather information on terror groups. Burns also stated that the Taliban are probably in the 'strongest military position that they have been in since 2001', following the US military drawdown.

In the interview, CIA director Burns also commented on Russia's overarching influence in world affairs. The director pointed that the intelligence service suspects Russia could be behind the 'Havana syndrome' which was affecting the health of US diplomats in Cuba. However, he added that there were no definitive conclusions and various possibilities.

As mentioned in agencies' reports, Havana Syndrome is a series of unexplained medical symptoms first experienced by State Department personnel stationed in Cuba beginning in late 2016. Since then, diplomats and other officials stationed around the world have experienced similar symptoms.