Hungary takes over the European Union's six-month rotating presidency on July 1, in the face of fears perennial spoiler Prime Minister Viktor Orban could use it to take the bloc hostage at a critical time.
EU leaders and diplomats have years of bitter experience dealing with Budapest's hard-right government on issues ranging from Ukraine aid to migration and the rule of law.
In his 14 years as premier, nationalist Orban has become expert in playing hardball — critics call it blackmail — with Brussels and has repeatedly wielded his veto to get more EU funds.