South Korea's $6 billion payment for Iranian crude oil has been frozen by the US administration again due to rising tensions regarding Iran's suspected links to the militant group Hamas, according to reports from multiple media outlets on Friday, including The New York Times.

These funds were originally intended for humanitarian assistance under strict US oversight. Now held in a Qatari bank, they are caught up in a diplomatic tangle following recent Hamas-initiated hostilities against Israel.

In a gesture of diplomacy, the US had previously planned in August to unfreeze these and other Iranian assets, especially after brokering a deal that secured the release of detained Americans in Iran.

However, with the shadow of Iran's potential ties to Hamas looming, key US figures, including former House Speaker Kevin McCarthy, have called for a more cautious approach towards releasing these funds, emphasizing the potential misuse of such revenues.

US Secretary of State Tony Blinken, during his recent visit to Israel, had confirmed that the aforementioned funds remain untouched in the Qatari bank. Furthermore, Senator Lindsey Graham has put forth the idea of a US-Israel collaborative strategy to curtail Iranian oil operations.

While there's no direct evidence tying Iran to the recent Hamas activities, the US remains cautious due to their historical relationship. Iran has denied any recent engagement or support for Hamas actions.