The European Commission has been urged not to “appease” Viktor Orbán by unfreezing billions of euros for Budapest, as the Hungarian prime minister threatens to derail EU plans to open accession talks with Ukraine and grant Kyiv fresh aid. The Hungarian government’s moves in recent years to undermine independent institutions, as well as concerns about corruption and alleged misuse of European funds, have led Brussels to withhold over €27bn (£23bn) earmarked for Hungary. However, in a step likely to fuel frustration among rule of law advocates, the commission has signalled that it may be prepared to unfreeze up to €10bn, ostensibly due to progress made on judicial reforms. The move comes before a meeting of European leaders scheduled for 14 December when the EU’s 27 heads of government are scheduled to discuss a proposed €50bn aid package for Ukraine, changes to the bloc’s budget and whether or not to greenlight the opening of accession talks with Kyiv. Hungary’s leadership has repeatedly threatened to block decisions on all three issues. In a letter seen by the Guardian to the European Council president, Charles Michel, Orbán reiterated his position. “I respectfully urge you not to invite the European Council to decide on these matters in December as the obvious lack of consensus would inevitably lead to failure,” he wrote, referring to Ukraine’s accession negotiations and the revision of the bloc’s budget. The emerging standoff has heightened fears among Orbán’s critics that the bloc will unfreeze some of Hungary’s funds in an effort to convince Budapest to sign off on the financial aid for Ukraine and the opening of accession talks. Daniel Freund, a German Green member of the European parliament and critic of the Orbán government, urged the EU on Monday not to let Hungary off the hook. “The Orbán government did not fulfil the necessary reforms,” he said. “No money must flow. If the commission decides otherwise, it is only for one reason: they’re trying to appease Orbán who went completely overboard with his veto threat.” In order to access the funds, Hungary must in theory complete a series of reforms in areas such as judicial independence, transparency and the fight against corruption. For months, Brussels and Budapest negotiated as Hungary introduced legislative changes. The commission now says a lot has been achieved on judicial reforms. And last week, a commission official told reporters that a decision could be taken which would lead to €500m being paid to Hungary in the coming weeks, and €10bn made available in the coming years. Nevertheless, in a joint analysis published mid-November, six leading Hungarian civil society groups said that “the judicial reform package adopted in May 2023 remains fundamentally deficient”. The group, which includes the Hungarian Civil Liberties Union and Hungarian Helsinki Committee, concluded that “three out of the four” judiciary milestones “are implemented defectively even at the level of the legal framework, and there are areas where further proof is required of the proper implementation of the milestones to verify compliance”. The Hungarian government did not respond to a request for comment. However, a senior Hungarian official, who was granted anonymity because they are not authorised to discuss the negotiations, insisted that “we’ve fulfilled the judicial milestones”. The issue of Ukraine, the official said, is “a matter of principle” for Orbán and the prime minister believes the country “is simply unable to meet the membership criteria”. An EU diplomat, who spoke on condition of anonymity to discuss sensitive internal matters, said they believed the decision to unfreeze would not be taken due to pressure over Ukraine. “The commission is moving on this because they have no other choice. If Hungary does the work on part of it, then the commission has little choice but to give the money,” the diplomat said. Orbán is “doubling down” on Ukraine and “it’s not about the money any more”, they added. Freund, the German parliamentarian, cautioned that unfreezing funds for Hungary at this stage could create a risky precedent. “If Orbán succeeds, others will follow his example and abuse their veto,” he said, adding: “It will significantly weaken the European Union in the future.”