BRUSSELS (AP) — The heads of the European Union's 27 member nations will meet Thursday in Brussels to discuss tougher sanctions on Russia, ways to prevent painful new U.S. tariffs, and how to make their voices heard in the Middle East conflicts.

Most of the leaders will arrive from a brief but intense NATO summit where they pledged a big boost in defense spending, and papered over some of their differences with U.S. President Donald Trump.

Ukrainian President Volodymyr Zelenskyy will join the EU summit by videoconference, after meeting Trump on Wednesday. U.S.-led NATO downgraded Ukraine from a top priority to a side player this week, but Russia's war in Ukraine remains of paramount concern for the EU.

Members will be discussing an 18th round of sanctions against Russia and whether to maintain a price cap on Russian oil, measures that some nations oppose because it could raise energy prices.

Meanwhile, Trump's threatened tariffs are weighing on the EU, which negotiates trade deals on behalf of all 27 member countries. He lashed out at Spain on Wednesday for not spending more on defense and suggested yet more tariffs. France's president called Trump to task for starting a trade war with longtime allies.

European leaders are also concerned about fallout from the wars in the Middle East, and the EU is pushing to revive diplomatic negotiations with Iran over its nuclear program.

EU members have internal disagreements to overcome. They are divided over what to do about European policy toward Israel because of its conduct in Gaza. And left-leaning parties are attacking European Commissioner Ursula von Der Leyen's pivot away from the EU's climate leadership in favor of military investment.

Defense and security are likely to top the agenda. The summit will end with a statement of conclusions that will set the agenda for the bloc for the next four months and can be seen as a bellwether for political sentiment in Europe on major regional and global issues.