New Delhi, Feb. 5 -- Iran and the United States are set to resume nuclear negotiations on Friday in Oman, returning to a diplomatic track derailed by Israel's 12-day war on Iran in June and a subsequent wave of nationwide protests that triggered a deadly crackdown by Tehran.

The talks come as President Donald Trump intensifies pressure on the Islamic Republic, warning of possible US military action if Iran pursues mass executions linked to the protests - and reintroducing Iran's nuclear programme as a central foreign policy battleground after months of regional escalation.

The Oman meeting is the latest attempt to revive negotiations over Tehran's nuclear programme after five rounds of talks in Rome and Muscat last year were disrupted b...