Ok some more thoughts on this.....
- The interviewee says Saudi Arabia has "a nuclear bomb" in the manner that you'd say we had "the bomb". That doesn't imply numbers in possession (like the 2 earlier discussed), but full width and breath of what it means to be nuclear capable. In digging around more, again the main references besides the RT Arabic interview with Dahham Al Anzi, sourced from MEMRI's site are "alternative media" other than the
interview on the Cavuto show on Fox Business with Duane Clarridge which as Clarridge saying that the Saudis having "dibs on 4 to 7" of the Pakistani weapons they helped pay most of the bill for developing and manufacturing.
- From all of this first no real surprise in the Saudis, or for that matter Iran, having nuclear capability, or access to it, for at the minimum the last decade. As I've often noted, we're talking about 1930s-40s physics and munitions engineering at its foundation. My "oh merde" moment was a statement I haven't found a collaborating source for (and if someone has it please post a link); that South Africa is directly involved and to what extent in this Saudi program for no other reason than the expansion of proliferation beyond the "Khan Network" (that Khan reportedly took it upon himself to "aid" Iran with information on fuel cycle technology (centrifuges) beyond the "civil technology" assistance that then Pres. Zia authorized while taking Saudi money to fund his nuclear program is "interesting" to say the least).
- The "unofficial" announcement by Al Anzi as a warning to everyone regarding the Kingdom's security in terms of Yemen and Syria does light off the warning lights, but it looks in a way as an act of desperation. If "everyone knows" they've got nuclear weapons what Al Anzi said is a thinly veiled exercise in "saber rattling" against a fully nuclear armed power that is already at war with the ideology the Saudis have been supporting ad nausea and they see as a direct threat already to the Russian people, any such direct threat would be stepping from the sidelines and onto the field proper.
- The Saudi missile forces, the Royal Saudi Strategic Missile Force (RSSMF), is an independent branch of the Saudi military that numbers 2500 personnel. It was set up initially in 1987 to counter the missile threat Iran posed as a result of the Iran-Iraq War. Saudi Arabia bought a "conventional warhead" armed version of the PRC's liquid fueled CSS-2/DF-3 IRBM, the DF-3A (3000 to 4000 km range throwing a warhead of up to 2150 kg/4730 lbs with a CEP of 1000 m).
Reportedly relying upon a cadre of "seconded" personnel from the PLA 2nd Artillery, the force started taking delivery of the missile and related support equipment in 1988. That force is suspected to be of between 30~120 missiles and 9~12 transporter erector launchers (TEL) and was first publicly displayed on Saudi TV in 2014.
In 2007, the KSA took delivery of an unknown number of PRC DF-21 solid fueled IRBMs (1,100 mile range throwing a 600 kg (1,300 lb) payload with a CEP of 30 meters). This deal was OK'd by the US on the understanding that they would be modified to not mount nuclear weapons like the DF-3As. The Saudis did not apparently buy the Chinese TELs that go with this system so either they are to be used at fixed sites or they're going to use the less capable TELs of the DF-3As.
With high explosive unitary or sub-munition warheads these systems are a threat to large facilities like petrochemical, industrial sites or airfields. Lobbing them at smaller targets like C4IR sites in the case of the older DF-3As would be a waste of resources and in the case of the DF-21s though effective, would open up Saudi Arabia and the other Gulf States to the vastly larger missile strike capability of the Iranians (conventional or nuclear).
Now if you add 4 to 7 nuclear weapons into that mix of missiles, that math changes, particularly if Iran actually did give up a reported nuclear capability. If on the other hand you're looking at Iran having perhaps a dozen nuclear weapons, you now have a MAD scenario comparable to that early on in the nuclear phase of the "warm war" between India and Pakistan. If you add a percentage of the Pakistani arsenal "dual tasked" with Iranian targets it gets even more interesting and a real stimuli for Iran to "nuke up".
- Now as to threatening the Russians in Syria with this missile force or a mix of these missiles and aircraft delivered weapons. The first problem the Saudis would have would be whether the Chinese still have a significant support role for their missile force. If they do then they potentially have a real veto power on their use akin to the "2 Key System" the US has with NATO allies.
Next is the degree to which the Russians have faith in the S-400 system they deployed to guard their main bases in Assad held territory. The coverage is such that the Russians would see the launch(s) and have an opportunity to intercept. As to aircraft, I'm guessing if they aren't there yet we're going to see a dedicated AWACS patrol over the area as well.
The biggest point is that the Russians, seeing the Syrian situation important enough to put an expeditionary force that far out from direct supply from Russia, including naval assets, they're deadly serious about their support for Assad and their minimum goals.
If all you can do is threaten that specific force and not the Rodina, IMHO the Russians are more than willing to pick up that thrown gauntlet. Even if the Saudis could put three weapons into key targets in Syria, in support of "moderate rebels", and had 4 to 7 left over to keep Iran at bay (or for that matter use them on Iran since they've already kicked over the table), the Russians would have no issues at all with using up a couple of their strategic systems launched out of Russia proper and probably overflying only Russian and allied airspace to respond in kind and more so in the same manner that the US has stated it would do if WMDs were used against its forces.
Such a Russian strike would be in a manner that would remove the KSA from the table and drop it into a full blown civil war because at the top of that targeting list besides the royal family would be the major bases of their military. With them gonr or severely compromised, the various factions within the country that are being suppressed would literally leap out of the ground to try to seize the place for themselves.