Former U.S. Ambassador to Ukraine, Eurasia Center Director at Atlantic Council John E. Herbst says it is necessary to supply more weapons to Ukraine, while the West should impose stronger sanctions against Russia to stop its aggression.

The diplomat says Russia and Putin pursue an aggressive foreign policy, as they want to undermine the world order set after the Cold War, Voice of America's Ukrainian service wrote on October 19.

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He added that ensuring a strong and stable world order is in line with the U.S. interests and values.

If we give up this world order, then let Russia carry out an aggressive policy against Ukraine and Georgia, he said.

According to the official, the West is still getting used to the idea that Russia is pursuing an aggressive foreign policy. "Our position today is much better than it was four years ago, but it's still not good enough. I think it will improve," the diplomat added.

In his opinion, Georgia, Ukraine and Moldova need more support. Moreover, it is necessary to impose stronger sanctions against the Kremlin for its aggression in Georgia and Ukraine. "The stronger sanctions will weaken the Kremlin. While the Kremlin is pursuing an aggressive foreign policy, it's in our interests that it become weaker. In addition, Ukraine needs more weapons, which will make further Russian aggression harder and more painful," he added.

Herbst says that everyone needs to realize that the Donbas events are the Kremlin's war and aggression against Ukraine.

To stop the Kremlin is extremely important, he says, adding that the front line is now in the east of Ukraine. It is in the interests of the West to stop the Kremlin's aggression in Donbas, which is the basis for providing a package of annual aid worth US$1 billion during five years for military equipment, the diplomat said. Such a package will meet the current requirements for anti-tank missiles, secure communications, modern drones, and anti-aircraft radars.

In the same vein, the U.S. should consult with Georgia on military needs. The United States, along with NATO allies, should consider increasing their presence in the Black Sea region, the diplomat added.