Relations between Russia and Ukraine are still raw after the annexation of Crimea four years ago.

Moscow has since been backing pro-Russia separatists in eastern Ukraine where fighting continues.

There are fears Sunday's confrontation in the Black Sea could lead to a wider conflict.

A Russian coastguard ship rammed a Ukrainian navy tug and opened fire on two other ships. Several Ukrainian sailors were wounded - more than 20 were taken as prisoners.

It happened in the Kerch Strait, off the coast of Crimea, a narrow stretch of water that links the Black Sea to the Sea of Azov, which is home to two of Ukraine's most important ports.

Russia says the Ukrainian naval vessels entered its waters illegally despite a treaty which guarantees freedom of navigation.

Ukraine calls it an act of "aggression" and has put its military into combat readiness.

But President Petro Poroshenko says Ukraine does not plan to fight anyone.

So, can the crisis be contained? Or will it escalate further?

Presenter: Adrian Finighan

Guests

Glenn Diesen - Professor of international relations at the Higher School of Economics in Moscow

Taras Kuzio - Ukraine expert and author of Putin's War Against Ukraine

Mychailo Wynnyckyj - Associate professor of the Department of Sociology and Business School at National University of Kyiv-Mohyla Academy

Source: Al Jazeera News