Saudi Arabian diplomats and military officials refused to meet with a bipartisan delegation of senior congressional staffers who visited the Middle Eastern country last week, an unusual snub that suggests increased tension between the U.S. and a key ally.

"Everyone on the trip definitely took it as a snub," one of the staffers who went on the trip, speaking on condition of anonymity, told the Washington Examiner. The delegation was comprised of "high level" staff from three House committees: Intelligence, Homeland Security, and Armed Services.

The staffer said that the delegation asked to meet with representatives of Saudi Arabia's Foreign Affairs Ministry and Defense Ministry during the weeklong trip, but the Saudis denied both requests. The rejection is especially unusual because the Saudis paid for the delegation's visit, but did not allow them to talk to their most natural counterparts in the Saudi Arabian government. The aide, who has visited the country multiple times on such delegations, said every previous trip featured a meeting with at least one of the two ministries.

The snub stems from Saudi anger over what they see as President Obama's weak response to the Syrian civil war and U.S. attempts to get a nuclear deal with Iran, according to the staffer. The Iranian negotiations are most troubling to the Saudis, according to the aide, saying they think Obama is being "shortsighted" in his strategy for preventing Iran from getting a nuclear weapon.

Gulf Arab states have been watching with grave concern Obama's hopes to negotiate an end to Iran's nuclear program, even as the regime gets closer to obtaining a weapon. Many, especially Saudi Arabia, see Iran's ambitions as an existential threat.

“Tehran has made technical progress in a number of areas -- including uranium enrichment, nuclear reactors, and ballistic missiles -- from which it could draw if it decided to build missile-deliverable nuclear weapons,” James Clapper, the director of National Intelligence, wrote in a report on global threats delivered Wednesday to the Senate Intelligence Committee. “These technical advancements strengthen our assessment that Iran has the scientific, technical, and industrial capacity to eventually produce nuclear weapons. This makes the central issue its political will to do so.”