Romanenko, former Deputy Chief of the General Staff of the Ukrainian Armed Forces, said Ukraine will not "sit idle" and will "defend their positions" if necessary.

A shipping dispute between Ukraine and Russia is at risk of escalating into a "great war" as Western nations seek to face down aggression from Vladimir Putin, a former Ukrainian general has warned.

Ukraine has accused Russia of harassing of ships and increasing its military presence in the Sea of Azov, a strategic ocean route linked to the Black Sea by the narrow Strait of Kerch, according to the Daily Star.

A dispute over access to the sea, shared by Ukraine and Russia, has provoked an acrimonious war of words, with both sides accusing each other of illegally detaining their ships.

Tensions over the thorny issue of access to the sea have escalated since Russia built a bridge, known as the Kerch Strait Bridge, linking the annexed Crimean Peninsula with the mainland.

Former Ukrainian lieutenant-general Igor Romanenko said the blocking of ships could prompt the West to impose further sanctions on Russia, which could have devastating consequences.

He said a "large-scale war" is possible if Russia continues to "aggravate the situation" in the Sea of Azov by conducting invasive inspections and seizing fishing ships.

Read alsoUkraine's defense minister responds to Russian threats to "shut down" Sea of Azov

Romanenko, former Deputy Chief of the General Staff of the Ukrainian Armed Forces, said Ukraine will not "sit idle" and will "defend their positions" if necessary.

However, he said Ukraine should be wary about resorting to military action because Russia has a superior army and "we will not be able to answer," he said according to various Russian and Ukrainian news outlets.

"In this case, you need to focus and translate the situation in a large-scale war, which is currently impractical for Ukraine," he said.

The tense situation in the Sea of Azov comes amid the backdrop of armed conflict between the Kyiv government and the Russia-backed separatist forces in eastern Ukraine.

As tensions simmer, Russia's foreign ministry issued a statement warning that "responsibility for possible further deterioration of the situation in the Azov-Kerch Strait area is with Ukraine and other states supporting its provocative actions."

In the statement, the ministry denied Russia was militarizing the Sea of Azov saying forces have been deployed for "guarding the Crimean Bridge."

Inspections of ships in the waters are legitimate and not discriminatory, the ministry added.

Russian lawmaker Frants Klintsevich, who sits on the defense committee in the upper house of parliament, said on November 16 that Russia could "cut off" the Sea of Azov "in minutes" in response to the detention of Russian ships.

"It doesn't matter if we are talking about the detention of Russian ships or ships of foreign states," he said.

"By such actions, Ukraine itself really breaks the agreement on the Sea of Azov, from which only it will suffer."

Meanwhile, UK defence secretary Gavin Williamson announced a series of military exercises and the deployment of more troops and a Royal Navy ship to Ukraine.

In a meeting with the visiting Ukrainian defence minister Stepan Poltorak, Williamson said the deployment would strengthen their military ties "in the face of intensifying threats and aggression" from Russia.

An unspecified number of British forces would be sent to train Ukrainian special forces and marines early next year, The Ministry of Defence (MoD) confirmed.

The HMS Echo, a hydrographic survey ship, will be deployed to the Black Sea region, complete with its crew of 72, the MoD said.

Williamson said: "As long as Ukraine faces Russian hostilities, it will find a steadfast partner in the United Kingdom."

"By continuing to work together, whether through training programmes or military exercises, we help Ukraine to stand up for our shared values.

"Those values of freedom and democracy cannot be traded."

"I have witnessed on the frontline the effects of the conflict in the East and this has completely reinforced my support for Ukraine's sovereignty, independence and territorial integrity."