Turkey is standing by its decision to purchase a missile defense system from Moscow, despite repeated threats from Washington. The U.S. has halted shipments of fighter planes in response, but Ankara remains defiant. Now Turkish officials are trying to strike a delicate diplomatic balance. But as CGTN's Michal Bardavid reports, keeping the two powers happy is no easy task.

Ankara has found itself stuck between two of its allies, Washington and Moscow, both of which are important for Turkey in many different ways, economically, politically, and in terms of security.

The issue of conflict is Turkey's purchase of an S-400 missile defense system from Russia – a move that the U.S. says compromises the F-35 Joint Strike Fighter program.

In response, Washington has recently announced it has halted the delivery of equipment related to the F-35 fighter aircraft to Turkey. The U.S. insists Ankara must choose between NATO or Russia but Turkey's Foreign Minister argues this cannot be expected of Turkey.

MEVLUT CAVUSOGLU TURKISH FOREIGN MINISTER "So, any country in our region, actually, has no other option but should balance its relations with everybody in the region. And our relations with Russia is not an alternative to NATO allies or not an alternative to our EU policy or our European partnership or ambitions."

MICHAL BARDAVID ISTANBUL "Turkish officials have repeatedly stated the S-400 agreement with Russia was a 'done deal' they cannot back out of. Meantime, U.S. Vice President Mike Pence has warned Turkey would risk expulsion from the F-35 program which he said would harm Turkey's defense capacity."

Some military analysts say Turkey will need to take its national security into consideration.

DR. NAIM BABUROGLU FACULTY MEMBER, ISTANBUL AYDIN UNIVERSITY "Turkey cannot give up on NATO, not under today's political circumstances. Turkey doesn't just need a missile defense system, it needs NATO's alliance umbrella. Turkey is under several threats, there's the East Mediterranean, the power struggle regarding energy security in the East Mediterranean, the Aegean issues, and also issues with NATO member Greece and the Southern Cyprus Greek administration."

However, if Turkey decided to withdraw from the deal with Russia that too would potentially have many negative effects regarding Ankara-Moscow ties. Turkey has been cooperating with Russia over the Syrian conflict where both countries are acting as guarantor states. Backing away from the deal could also hurt Turkey's image.

DR. NAIM BABUROGLU FACULTY MEMBER, ISTANBUL AYDIN UNIVERSITY "If Turkey, a serious country with regional power and rooted history walks back on a deal it has signed, that would cause a negative impact, it could damage its prestige and reputation."

There could be economic consequences as well. Following a dispute with Washington last year, Turkey's economy had taken a hit - an escalation of tension with NATO allies could once again trigger a crisis.

As Turkey tries to find a balance between Washington and Moscow, it seems Ankara will find it difficult to keep both sides happy and will need to find a solution to this issue, but which way it will go, who will make the compromise is yet to be seen. The S-400 deal will likely be top of the agenda for Turkish President Recep Tayyip Erdogan who is headed to Moscow to meet with his Russian counterpart Vladimir Putin on April 8th. Michal Bardavid, CGTN, Istanbul.