Is Russia’s military move into separatist-held eastern Ukraine an invasion?

The Ukraine crisis has entered a new phase after Russia authorised sending “peacekeeping” troops into eastern Ukraine this week, recognising two breakaway regions as independent states. 

Western states called the Russian move “a flagrant violation of international law” but were split over calling it an invasion. 

“I wouldn’t say that (it is) a fully fledged invasion, but Russian troops are on Ukrainian soil,” said EU foreign policy chief Josep Borrell in Paris, in contrast to the US and NATO, which described it as an invasion. 

Even the US initially did not want to call it an invasion seeing it as “ongoing escalation along the borders of Ukraine” because separatists already controlled the breakaway regions and Moscow has covertly backed them since 2014. But after a brief reluctance, President Joe Biden called the Russian move “the beginning of a Russian invasion of Ukraine.” 

“What we see now is that a country that is already invaded is suffering further invasion,” said NATO Secretary-General Jens Stoltenberg. 

Experts also seem divided over the definition of the recent Russian military deployment. Western leaders claim that they have already entered Ukraine. 

“I would not characterise Putin's action as an ‘invasion.’ It is very similar to Adolf Hitler's annexation of Austria in March 1938 (historians call this the Anschluss), which was a peaceful occupation of a country largely sympathetic to the Nazis,” says Edward Erickson, a former US army officer and a retired professor of Military History from the Department of War Studies at the Marine Corps University. 

“Sending in the Russian army into the areas already held by Russian separatists doesn't change much in the Donbass. However, if the Russians attempt to take new territory in Ukraine, then it most assuredly is an ‘invasion’,” Erickson tells TRT World. Ukraine’s eastern Donbass region includes the two separatist regions of Donetsk and Luhansk.  

Enver Arikoglu, an associate professor of international law at Istanbul University, believes it is an invasion, on legal grounds, but explains the reluctance to call it that. “I believe why Borrell and others do not want to define the Russian deployment into eastern Ukraine as an invasion is related to their political concerns,” Arikoglu tells TRT World. 

What does international law say?

To define a state’s act as an invasion, international law determines whether a state violated the prohibition of the use of force against another state with its military action, according to Arikoglu. 

“The question is whether Russia has illegally used force against Ukraine by violating its sovereignty and territorial integrity. If so, Russia is an invader, according to international law,” Arikan observes. 

Russia refers to its troops in eastern Ukraine as “peacekeeping” forces, being careful to indicate that they will be in areas which were declared by separatists as parts of their breakaway republics. It’s not clear yet that any Russian troops officially entered the rebel-controlled region. 

In international law, a state’s sovereignty and territorial integrity is considered as “sacrosanct”, meaning sacred and inviolable, as a result, no outside power can interfere in a state’s internal matters, says Arikoglu. 

But it does not mean that some groups inside a state can not start a rebellion against the state’s political authority. In that case, outside powers still should not back such a rebellion against that state, says the professor. 

In 2014, in eastern Ukraine, separatists launched a rebellion against Kiev’s authority backed by Moscow. Since then, they have controlled their breakaway regions and this week Russia authorised sending troops to protect them against Ukrainian operations. 

“Other states can help rebels if they are under colonial rule, according to international law,” Arikoglu says, but Kiev’s rule over the Donbass region, where Russians are even not a majority, clearly has nothing to do with colonialism. Even Vladimir Putin thinks that Ukraine was formed thanks to the generosity of communist Soviet leaders, preceding Russia.

As a result, Russian interference in eastern Ukraine to protect breakaway states is a violation of international law, he says, because the legitimate government is entitled to use force against a rebellion. 

‘Effective control’

Russian recognition of separatist regions is also in contravention of international law due to the principle of “effective control” , says Arikoglu. If rebels in a given country are able to sustain “the continuity of effective control” over a particular region for years, using their own means without outside help, other states can recognise their independence, according to the professor. 

“If pro-Russian rebels’ activity in eastern Ukraine reached a level of the continuity of effective control without outside help and Ukraine lost its hope to regain those breakaway regions, then, other states like Russia could recognise them as independent states,” says the professor.  

“But this argument is a weak argument because their control has been clearly enabled by Russians according to various data,” he says. As a result, Russia’s recognition of the breakaway regions in Ukraine is “an early recognition” that international law finds a wrongful act. The Russian “proposition to use force” to protect separatists is also illegal, he adds. 

Under current circumstances, Russian action in eastern Ukraine could be considered as “an invasion”. As a result, he finds Borrell’s comment political, but problematic.

Because Russia is one of the permanent members of the UN Security Council, Moscow has no fear that it might face international isolation and widespread sanctions, Arikoglu says. “Like the US invasion of Iraq, Russians think that they could also launch their own invasion by using sheer force,” the professor concludes.