BRUSSELS: A row over Poland’s bid to replace European Union President Donald Tusk threatens to overshadow a summit this week that was meant to focus on post-Brexit unity.

Most of the 28 EU leaders had hoped to push through Polish ex-premier Tusk’s re-election with a minimum of fuss so they could concentrate on other challenges.

But instead, the two-day summit starting Thursday risks being consumed by splits along old east-west lines as the Euro-sceptic Polish government proposes a rival candidate, with support from Hungary.

The leaders also face rifts over Britain’s exit as they meet without Prime Minister Theresa May on Friday to draw up plans to mark the EU’s 60th birthday in Rome later this month.

Unity is at a premium for the EU as it deals with Britain’s departure, Russian aggression and new US President Donald Trump.

Centrist former Polish premier Tusk has broad support among the leaders for a second mandate until 2020 for his handling of crises including migration and Greek debt.

As leader of the European Council he heads the body that groups the 28 national leaders of the EU, and hosts Brussels summits.

But Poland’s right-wing governing Law and Justice party surprised many by suddenly proposing Euro-MP Jacek Saryusz-Wolski instead of Tusk, its long and bitter foe.

“Tusk has a very strong position,” an EU official told AFP, as Poland has no veto in the decision and is likely to be supported only by Hungary, led by the Euro-sceptic Viktor Orban.

Under EU rules it would need a majority of at least 72 per cent of the 28 leaders, representing at least 65 per cent of the EU population, a European Council official told AFP.

Growing split

But there is disquiet at the way an internal political feud has spread to the European stage at a time when it is meant to be giving the impression of unity.

“I think we will leave our Polish friends to face the cold wind alone,” an EU diplomat told AFP on condition of anonymity.

Tusk has been at odds with Law and Justice for years, especially its chief, Jaroslaw Kaczynski, who accuses him of “moral responsibility” for his twin brother and then-president Lech Kaczynski’s death in a 2010 plane crash in Russia.

The Tusk issue highlights a growing split between the older, western EU nations and the poorer, newer countries in the East, especially on issues such as migration.

This is also likely to figure when 27 EU leaders meet without Britain on Friday to discuss the March 25 summit in the Italian capital marking the 60th anniversary of the EU’s founding Treaty of Rome.

They are finalising a special declaration on shoring up EU unity after Brexit, but there are divisions about whether this should back a so-called “multi-speed Europe.”

The “big four” EU economies — Germany, France, Italy and Spain — said at a meeting in Versailles on Monday that they supported countries being able to integrate at different speeds.

“Unity does not equal uniformity,” French President Francois Hollande said after the talks.

But Eastern European nations have strongly opposed any such move.

Polish Prime Minister Beata Szydlo said last week that they “never will” agree to such divisions while Slovakian premier Robert Fico said preparations for Rome were “pathetic”.

“The key message in Rome should be unity. The conclusion from Brexit should not be ‘we need more multi-speed Europe’,” a European diplomat said on condition of anonymity.

Meanwhile the EU leaders will also discuss a fresh challenge in the form of instability and growing Russian activities in the Western Balkans.

The EU leaders are likely to warn in a statement against “external destabilising influences” but Moscow itself will not be specifically named, diplomats said.