U.S. national-security adviser John Bolton says the Iranian oil tanker released last month from detention in Gibraltar and still sought by U.S. authorities has arrived in the Syrian port of Tartus.
Early on September 7, Bolton tweeted a satellite image dated September 6 that appeared to show the recently renamed Adrian Darya 1 under partly cloudy skies off the coast of Tartus.
"Anyone who said the Adrian Darya-1 wasn't headed to #Syria is in denial," Bolton said on Twitter.
Tehran has insisted for months that the supertanker formerly named Grace 1 was not bound for Syria.
Authorities in Gibraltar detained the Grace 1 and its suspected 2 million barrels of oil in July on suspicion it was carrying oil to Syria in violation of EU sanctions before releasing it weeks later.
Renamed the Adrian Darya 1, it has spent the past two weeks in a cat-and-mouse game as U.S. officials who allege it has ties to a "terrorist" arm of the Iranian military warn European ports from providing it any assistance.
The widely used AIS system for tracking such vessels stopped receiving signals from the Adrian Darya 1 on September 2, according to VesselFinder.com.
Bolton's image put the massive supertanker about 2 nautical miles from the Tartus naval facility in Syria used by Russia to help support Moscow and Tehran ally President Bashar al-Assad in his ongoing eight-year war against armed opponents.
"Tehran thinks it's more important to fund the murderous Assad regime than provide for its own people," Bolton added. "We can talk, but #Iran's not getting any sanctions relief until it stops lying and spreading terror!"
Washington and Tehran have been locked in dispute as U.S. sanctions reimposed last year after the United States withdrew from a 2015 nuclear deal and additional measures intended to apply "maximum pressure" on Iran's leadership continue to pound that country's economy and currency.
Iranian news agencies said on September 7 that the country's coast guard forces had seized a vessel in the Persian Gulf and detained its 12 crew members. Authorities accuse the ship -- reportedly a tugboat -- and its Filipino crew of smuggling fuel.
On September 5, Iran freed seven of 23 crew members of a British-flagged oil tanker that Iranian naval forces seized in July, soon after the Grace 1's detention. Tehran has accused that vessel's crew of breaking international maritime law, a charge the Stena Impero's owner and operator deny.
The U.S. State and Treasury departments on September 4 exerted further pressure on Iran with additional sanctions and monetary rewards for "actionable" information on what they call Tehran's "oil-for-terror" network.
Tensions have also risen over Iran's nuclear activities.
Tehran on September 7 unveiled its most recent steps away from the so-called Joint Comprehensive Plan of Action (JCPOA) between Tehran and world powers to limit Iran's nuclear program in exchange for sanctions relief, saying it was using advanced centrifuges in a way that could mark an effective exit from the deal.
The United States abandoned the JCPOA last year, but European signatories along with China and Russia have sought to keep it alive.