In the past three months, Iran has held several rounds of talks with the International Atomic Energy Agency, and the P5+1 countries -- China, the US, France, Russia, Britain and Germany.

In February, the EU joined the talks in Almaty in Kazakhstan. Iran’s chief negotiator, Saeed Jalili, called the meeting a "turning point", and described potential concessions on the table, including the easing of sanctions, as more "realistic."

At an IAEA meeting on March the 4th, the US dropped its plan to take the Iran nuclear issue to the UN Security Council. The P5+1 also issued a statement saying the problem should be solved through diplomatic means.

Two weeks later, Iran and the six powers held expert-level talks in Istanbul. They were described as "positive", although no major breakthrough was reached. Iran says it’s now able to enrich uranium to 20 percent purity. But there’s concern that could be a major step towards producing weapons-grade uranium. Iran denies the charge, saying its program is purely for energy and medical purposes.