The UK is included in this treaty and the decision to lift the sanctions.
The P5+1 refers to the UN Security Council's five permanent members (the P5); namely China, France, Russia, the United Kingdom, and the United States; plus Germany. The P5+1 is often referred to as the E3+3 by European countries.
"The United States would accept an invitation from the European Union High Representative to attend a meeting of the P5+1 [permanent members of the UN Security Council and Germany] and Iran to discuss a diplomatic way forward on Iran's nuclear program," said State Department spokesman Ned Price.
Washington has said it would consider a return to the 2015 nuclear deal abandoned by the Trump administration. Iran replied it's ready to comply with the agreement as soon as the US lifts sanctions.
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