EVEN as political relations between Russia and Ukraine have worsened of late, spiritual relations between the two main poles of authority in eastern Christianity have also taken a dive this month. They will probably sink further.

The occasion of the plunge is the desire of Ukraine’s elected leaders to establish a legitimate, national church, and the countervailing determination of Russia’s spiritual authorities, which are close to its earthly ones, to block that move. Ukraine’s president, Petro Poroshenko, has appealed to the Istanbul-based Ecumenical Patriarch, Bartholomew I (pictured above right), to bless the creation of a Ukrainian national church; Patriarch Kirill of Moscow (pictured above left) is insisting that the Istanbul-based authority has no right to interfere in what he regards as Muscovite canonical territory.

Patriarch Bartholomew is no less adamant that he has a duty of stewardship over church affairs in Ukraine, both because of his position as first among equals in the global Orthodox hierarchy and for specific historical reasons to do with the complex, shifting role of Constantinople’s bishops in the affairs of the eastern Slavs in Byzantine and even Ottoman times.

On September 7th the Ecumenical Patriarch took the first steps towards granting the wishes of Mr Poroshenko and his fellow legislators. He mandated two North American bishops to act as his representatives in preparing the way for a fully self-governing church in Kiev.

That will not be easy. As of now, the most widely organised church in Ukraine is one that owes allegiance to Moscow, sometimes called the Ukrainian Orthodox Church-Moscow Patriarchate (UOC-MP). The second most extensive is the Kiev Patriarchate (KP) which enjoys no international recognition. Presumably the creation of a national church would involve conferring a higher status on the KP and encouraging parts of the UOC-MP to join the upgraded structure. (The UOC-MP has far more priests and monasteries under its sway, but polls suggest that the KP is much more popular among the 70% of Ukrainians who identify as Orthodox.)

The Patriarchate of Moscow is furious. In a first raft of sanctions, Patriarch Kirill of Moscow declared that his church would cease to pray publicly for Patriarch Bartholomew. It was announced that neither the Russian Patriarch nor any bishops under his authority would celebrate the Eucharist (Christianity’s holiest rite) with bishops under the command of Patriarch Bartholomew. These are gestures of huge symbolic importance. It was made clear that if the Ecumenical Patriarch blesses the full independence of a Ukrainian church, there would be a total rupture of communion between the Patriarchates of Constantinople and Moscow. That would mean that ordinary clergy of the respective churches could not serve together and ordinary adherents of one church might be denied communion in the other. The 12 other self-governing churches which make up world Orthodoxy would face an awkward choice between the two Patriarchates.

Russian television showed a solemn and indignant Patriarch Kirill, surrounded by his senior bishops and communicating with his chief ecclesiastical ally in Kiev, Metropolitan Onufry, by video link-up. Patriarch Kirill icily listed the alleged misdeeds of the Istanbul-based Patriarchate over the centuries, focusing on the 1920s when the Istanbul-based authority parleyed with an ultra-modernist faction of the Russian church which was close to the Bolsheviks: this was a move which later generations of Orthodox deemed a mistake.

The Patriarchate of Constantinople, meanwhile, published documents which look embarrassing for the pro-Moscow bishops in Ukraine. They show that in 1991, as Ukraine was establishing its political statehood, the idea of full spiritual independence was supported by virtually all the country’s Orthodox bishops, including the ones who later changed their minds and accepted Moscow’s continued authority.

Formally speaking, the two Patriarchates are arguing over the legitimacy of a letter sent by the Patriarch of Constantinople in 1686, which accepted the transfer to Muscovite authority of the see of Kiev. The Ecumenical Patriarch says this transfer was provisional and subject to conditions that were not kept; the Muscovites repeated on September 14th that the transfer was clear and irrevocable.

But closely linked to these ancient historical disputes are some present-day political and geopolitical ones. President Poroshenko apparently sees the establishment of a national church as crucial to his political future. As a result, arcane words like “tomos” (a Patriarchal decree proclaiming an independent church) have become part of everyday political chatter in Kiev.

For the political as well as the spiritual authorities in Moscow, it would be humiliating to “lose” Ukraine. By one count, about half the total number of parishes under the authority of the Patriarchate of Moscow are in Ukraine. By no means all the people or clergy who pray in those parishes are strong sympathisers with Moscow. But the spiritual link between Moscow and Ukraine is one of the main levers of Russian influence over Ukraine, as President Vladimir Putin, a close friend and ally of Patriarch Kirill, well knows.

Meanwhile, the United States has made a subtle gesture of support for President Poroshenko over religious matters. Its religious-freedom envoy, Sam Brownback, met Mr Poroshenko on September 11th and listened with sympathy to his complaint that in areas of Ukraine “occupied” by Russia since it started backing separatists there in 2014, all churches other than the Moscow Patriarchate have been persecuted. Mr Poroshenko also outlined his hopes for an independent church that would operate freely, without persecuting others, in the Ukrainian lands that he controls.