World leaders are reacting to Democrats' comprehensive midterm wins, which saw them retake the Senate and flip the House on Tuesday night.

Why it matters: The results could reshape President Trump's final two years in office, with major implications for U.S. relations with allies and adversaries alike.

Zoom in: As Trump faces competing calls over whether to resume military action in Iran, Iranian officials supported the Democratic victories as a sign of opposition to the war.

  • Iran's Parliament Speaker Mohammad Bagher Ghalibaf wrote on X, "Conscience or the cost of living, Americans said NO TO WAR, and we endorse this message."
  • Prior to the election, regional mediators led by Qatar were trying to reach a diplomatic deal to restart negotiations between the U.S. and Iran to avoid reentering the war, three U.S., Israeli and regional sources said, but renewed fighting remains on the table.
  • But while Israeli Prime Minister Benjamin Netanyahu wants to resume fighting in Iran, his political future remains uncertain, with neither bloc securing the 61-seat majority needed to form a government in Israel's recent election.

Zoom out: Trump's second-term decisions have significantly strained relationships with U.S. allies and partners, leading countries to increasingly view Washington as unreliable, self-interested and less committed to global cooperation, according to Pew Research Center data.

  • But Tuesday's election results appear to have infused renewed hope about relations from international leaders.
  • Spanish Prime Minister Pedro Sánchez applauded Americans for voting "against policies that only make people poorer," and against "hate," "sexism," "climate denial" and "elite privilege," in a post on X."

South African President Cyril Ramaphosa told reporters he believes Democratic control of Congress will "introduce a new era in world relations," adding that he hopes for improved collaboration on geopolitics, trade and investment, Bloomberg reported.

  • Trump, who has repeatedly criticized Ramaphosa, and prioritized South Africans for refugee admissions in fiscal year 2026, citing debunked "white genocide" claims — which falsely allege that white Afrikaners face racial violence by the country's majority Black population.

The other side: Moscow signaled little optimism about the change in power, warning that Democratic control could further strain U.S.-Russia relations, particularly with tensions in Ukraine.

  • Deputy Foreign Minister Sergei Ryabkov told RIA Novosti news network that Democrats' "approach to relations with Russia is extremely negative."
  • Chinese Foreign Ministry Spokesperson Mao Ning struck a measured tone, saying China hopes to "build a constructive relationship," and continue working with the U.S.
  • Still, the U.S. Army Pacific is closely watching for a potential Chinese invasion of Taiwan in 2027 and beyond, which could quickly devolve into a bloodbath.

Yes, but: Some leaders are also questioning how much progress Washington can make amid such deep political splits.

  • Theo Francken, Belgium's Minister of Defense and Foreign Trade, said on X that governing in the U.S. will be "quasi impossible in the coming years with so much internal division and polarized power bastions."
  • European Parliament Vice President Christel Schaldemose said she's "cautiously optimistic on Europe's behalf" and how it could benefit Ukraine and global relations.

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