The latest batch of leaked emails from the United Arab Emirates ambassador to the United States Yousef al-Otaiba has revealed the extent of influence the UAE held over various US think-tanks, and in turn US foreign policy.

The Intercept reported that Otaiba, through the UAE embassy in Washington, DC, had gained substantial favours from Obama administration veterans by paying them handsome sums of money.

The emails are part of a collection of hacked correspondence leaked last month belonging to Otaiba’s Hotmail account, which he had used for official business.

One of the documents obtained was an invoice from an influential national security think-tank, which billed the UAE embassy for research papers in return for facilitating the UAE’s purchase of large military-grade weapons from the Missile Technology Control Regime.

Under former President Barack Obama’s term, the MTCR prohibited the sale of such weapons beyond the US’ closest allies. However, the Center for New American Security think-tank was part of a campaign to allow the UAE to buy these weaponries, specifically drones, The Intercept reported.

The CNAS had billed an invoice to the UAE embassy for $250,000 for a paper on "the legal regime governing the export of military-grade drones".

Michele Flournoy, a senior Pentagon official in the Obama administration, wrote an email to Otaiba on June 24, 2016.

"Yousef: Here is the CNAS proposal for a project analysing the potential benefits and costs of the UAE joining the MTCR, as we discussed," she wrote. "Please let us know whether this is what you had in mind."

Otaiba replied two weeks later.

"Thank you for the report," he wrote. "I think it will help push the debate in the right direction," referring to moving his country’s agenda forward.

In a different set of emails, Flournoy asked Otaiba to intervene in his country’s interior ministry in order to assist in the promotion of selling electronic surveillance technology from a US-based firm, Polaris Wireless, to the UAE.

It is not clear where the hackers, who refer to themselves as "GlobalLeaks", are from but they responded to The Intercept’s inquiry by saying they were "not affiliated with any country or religion".