EU three

The EU three, also known as EU big three or EU trio, refers to Germany, France and Italy, a group that consists of the three large founding members of the European Union; or France, Germany, and the United Kingdom, a group of countries of the European Union, especially during the negotiations with Iran.

In 2003, France, Germany and the UK launched negotiations attempting to limit the Iranian nuclear program, which led to the Tehran Declaration of 21 October 2003 and the voluntary Paris Agreement of 15 November 2004.

"EU 3 + 3", more commonly referred to as the "E3+3", refers to a grouping which includes the EU-3 and China, Russia, and the United States. It was coined when these states joined the EU diplomatic efforts with Iran in 2006. In the United States and Russia, it is more commonly known as P5+1, which refers to the five permanent members of the UN Security Council plus Germany.

"E3/EU+3") refers to a grouping of the "E3+3" plus an EU representative, namely: China, France, Germany, the Russian Federation, the United Kingdom and the United States, with the High Representative of the European Union for Foreign Affairs and Security Policy.

Following the 2004 enlargement of the European Union, the EU-3 group had a declining influence in the European Union other than in negotiations with Iran, and has acted more often within the G6.

Determined to keep the project intact in the wake of the UK’s vote to leave the European Union in 2016, France, Germany and Italy re-emerged as the "Big Three" and called for greater integration in various trilateral summits in Berlin, Paris and Ventotene.

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