Poland’s requests for changes to a European Union treaty on institutional reforms are causing concern in EU capitals which fear that a forthcoming summit intended to complete the treaty with a flourish, may turn instead into a flop.

EU governments want to put the finishing touches to the document in Lisbon on October 18-19, ending an ordeal that began in 2005 when Dutch and French voters rejected an earlier and grander version of the so-called Reform Treaty.

“It will be a political nightmare if we don’t get this right in Lisbon,” said one diplomat involved in preparations for the summit. “The public won’t be fooled.”

Some of the EU’s 27 countries are nervous that the conservative Polish government, now campaigning for a general election on October 21, will be in no mood to cut a deal before or during the summit.

These fears intensified after the atmosphere turned sour at a meeting of EU interior and justice ministers in Brussels last week, where the main topic was whether to declare October 10 a “European day against the death penalty”.

Poland, a predominantly Roman Catholic country whose government is alone in opposing such a declaration, caused astonishment by vehemently attacking the liberal pro-abortion policies of other EU governments, diplomats said.

The Poles wanted the EU to take a firm stand against abortion and euthanasia, but at least two other ministers in Brussels described their attitude as arrogant and far from the spirit in which EU business is normally conducted.

Although capital punishment is not on the agenda of next month’s summit, the suspicion and antagonism between Poland and its EU partners that were exposed by last week’s meeting show every sign of persisting.

According to EU experts, one problem is the need felt by Poland’s ruling Kaczynski twins - Lech, the president, and Jaroslaw, the prime minister - to demonstrate that their country, which joined the EU in 2004, will be no soft touch when it comes to defending Polish interests.

”There are similarities with the way that Spain stood up for itself after it joined in 1986. Like Poland today, Spain wasn’t as big as Germany, France, the UK or Italy, and wanted to make a point,” one diplomat said.

Ahead of the Lisbon summit, Poland has put forward three main demands. The most important is that the treaty should enshrine in law a member-state’s right to delay for ”a reasonable time” an initiative backed by a majority of other states.

Under current EU practice, a country can delay a decision for a maximum of three months, but this arrangement has no formal legal status.

Poland at first requested the right to delay decisions for up to two years. It later dropped this demand, but said it defined ”a reasonable time” as the time needed to forge a consensus among EU governments. Other countries fear Poland’s stance could paralyse the EU’s complicated decision-making procedures.

Poland’s second request is that, like the British, French, Germans, Italians and Spanish, it should have its own permanent senior official, known as an advocate-general, on the European Court of Justice. This would implicitly acknowledge Poland as the equal of the other five big states.

A third request concerns projects involving the European Investment Bank that have a non-EU dimension. Poland wants the EU to retain the system of unanimous voting used in such projects, rather than switch to majority voting.

The main practical effect would be to enable Poland to restrict the bank’s involvement in a Baltic Sea gas pipeline project backed by Germany and Russia and disliked by the Poles.

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