The following is a selection of reactions from around the globe to Trump's biggest foreign policy move since taking office:

- 'Psychological warfare' -

"This decision was an act of psychological warfare against Iran."

-- Iranian President Hassan Rouhani

- Uranium enrichment to resume? -

"I have instructed the Iranian Atomic Energy Organization to take the necessary measures for future actions so that, if necessary, we can resume industrial enrichment without limit."

-- Rouhani

- Stay the course -

"Stay true to your commitments as we will stay true to ours and together with the rest of the international community, we will preserve this nuclear deal."

-- European Union diplomatic chief Federica Mogherini

- 'Regret' -

"France, Germany and the UK regret the US decision to leave the JCPOA. The nuclear non-proliferation regime is at stake. We will work collectively on a broader framework, covering nuclear activity, the post-2025 period, ballistic activity and stability in the Middle East, notably Syria, Yemen and Iraq."

-- French President Emmanuel Macron, on Twitter, referring to the Iran deal by its formal name, the Joint Comprehensive Plan of Action

- 'Disappointed' -

Moscow is "deeply disappointed by the decision of US President Donald Trump to unilaterally refuse to carry out commitments under the Joint Comprehensive Plan of Action."

-- Russia's foreign ministry

- 'Instability' -

"The unilateral withdrawal of the United States from the nuclear deal is a decision that will cause instability and new conflicts."

-- Ibrahim Kalin, spokesman for President Recep Tayyip Erdogan, on Twitter

- Breaking commitment -

Damascus "strongly condemns the US president's decision to withdraw from the nuclear deal with Iran, which shows once again that the United States is not honoring its commitments and international agreements."

-- Syrian foreign ministry source quoted by the official SANA news agency.

- Compliance -

"I call on other JCPOA participants to abide fully by their respective commitments under the JCPOA and on all other member-states to support this agreement."

-- UN Secretary General Antonio Guterres

- 'Bold decision' -

"Israel fully supports President Trump's bold decision today to reject the disastrous nuclear deal with the terrorist regime in Tehran."

-- Israeli Prime Minister Benjamin Netanyahu

- Support from Saudi -

"The kingdom supports and welcomes the steps announced by the US president toward withdrawing from the nuclear deal... and reinstating economic sanctions against Iran."

-- Saudi Arabia's foreign ministry

- 'Misguided' -

"The reality is clear. The JCPOA is working... That is why today's announcement is so misguided... I believe that the decision to put the JCPOA at risk without any Iranian violation of the deal is a serious mistake."

-- former US president Barack Obama, whose administration brokered the 2015 deal