WASHINGTON — “BBC Newsnight,” a British equivalent of ABC’s “20/20,” ran a story on Nov. 6 saying intelligence reports judged that Pakistan was ready to deliver nuclear weapons to Saudi Arabia. The purpose would be to counter Iran’s perceived nuclear weapons program: “It is now possible that the Saudis might be able to deploy such devices more quickly than the Islamic Republic [of Iran],” the report concluded.

The implicit message was that Riyadh had a fallback option in case a deal is cut with the Islamic Republic that is not to its liking. Some may be skeptical about the report due to the denials of both nations and some vagueness about the source of these claims, but dismissing the report out of hand would be foolhardy: The outline of the “Newsnight” story has been circulating among Saudi watchers for several months as Riyadh’s frustration with Washington over its Middle East policies have grown.

Although the latest information does not appear to have come from Saudi Arabia — an unnamed “senior NATO decision-maker” was cited as the principal source — any transfer of Pakistani warheads or missiles would fit neatly into the category of “ways the House of Saud could make things unpleasant for Washington.”

Well before the uprisings of the so-called Arab Spring, King Abdullah regarded the threat of a nuclear Iran as a major destabilizing force. In February 2012, a correspondent of the London Times was summoned to Riyadh, where he was told by an unnamed senior Saudi official that the kingdom could acquire nuclear warheads “within weeks” of Iran developing atomic weapons. In the event of a successful Iranian nuclear test, Riyadh would “immediately launch a twin track nuclear weapons program,” according to the Saudi source, while warheads would be purchased “off the shelf” from abroad.

The collaboration between Saudi Arabia and Pakistan on Islamabad’s nuclear program has deep roots that could go as far back as the early 1970s, when Saudi King Faisal agreed to fund what is now the main mosque in the Pakistani capital of Islamabad. Riyadh was almost certainly also tapped for funds by then Prime Minister Zulfikar Ali Bhutto to pay for Pakistan’s uranium enrichment program in the mid-1970s — when the enrichment plant was revealed in 1979, diplomats and journalists in Islamabad saw the kingdom as one of the only likely sources of funds for such a project. The head of Pakistan’s nuclear program, A.Q. Khan — who was later condemned for proliferating nuclear technology to Iran, Libya, and North Korea — told me he visited the kingdom more than 40 times and was offered citizenship by one of King Abdullah’s half-brothers.

In 1999, Khan hosted Saudi Defense Minister Prince Sultan at the Kahuta uranium enrichment plant outside Islamabad, along with Pakistani premier Nawaz Sharif and Army chief Gen. Pervez Musharraf. The general would overthrow Sharif a few months later, sending him into exile in Saudi Arabia. Sultan saw more than Kahuta’s enrichment centrifuges: He was also shown a mock-up of the Pakistani bomb.

Some may expect U.S. intelligence to know every in and out about such dealings, but Washington’s knowledge of Saudi military planning has not always been perfect. In 1988, the kingdom took delivery of Chinese CSS-2 missiles even before Washington realized that Saudi Arabia and China had inked a deal two years earlier. The missiles were spotted by a U.S. satellite being trucked to launch sites south of Riyadh, having been flown in on giant transport aircraft.

Those missiles, previously part of China’s nuclear strike force, were arguably already obsolete, being liquid-fueled with unstable industrial alcohol and nitric acid. The immediate fear in Washington and other Western capitals was that they had come with nuclear warheads, though Riyadh insisted that they only contained conventional explosives.

Last week’s reported schism between Riyadh and Washington was supposedly patched up by the visit of Secretary of State John Kerry to Riyadh. According to former Saudi intelligence chief Prince Turki al-Faisal, addressing a private group in Washington last week, the two men “exchanged the frankest words ever.”

But all the frank talk in the world may not convince Riyadh to back down if it believes Iran is on the path toward a nuclear weapon. The best the Obama administration can probably hope for at the Geneva talks is to convince Iran to place restrictions on its nuclear program — actually stopping it seems increasingly unlikely without the use of military force. In these circumstances, the Saudis may well judge that the years of preparation they have devoted to going nuclear were well spent.

Simon Henderson is director of the Gulf and Energy Policy Program at the Washington Institute for Near East Policy.