Direct proof of use
The 4K51 Rubezh appears in the 2014 Yemen Civil War as captured Yemeni coastal-defense materiel held by Houthi-aligned forces. The Iran Primer / USIP lists the Houthi Rubezh anti-ship cruise missile as a P-21/P-22 equivalent seized from the Yemeni Army, and The War Zone reports that Yemeni government P-21/P-22 stocks ended up in Houthi hands after the group seized Sanaa and other areas in 2014.
The clearest public visual confirmation came at Hudaydah on 1 September 2022. The UN Panel of Experts on Yemen reported that Houthi forces displayed four anti-ship missile types at the parade and identified one as a Rubezh, a P-15 Termit coastal anti-ship missile exported to Yemen before the conflict. The Panel also cautioned that some displayed systems, including the P-15 Termit, might not have been operational.
Sources: Iran Primer Houthi Arsenal, TWZ Houthi Anti-Ship Arsenal, UN Panel Yemen 2023 Final Report
Dated milestones
The acquisition phase followed the Houthi takeover of Sanaa and other Yemeni military positions in 2014-2015. CTC analysis states that Ansar Allah took control of Yemen's coastal missile batteries in 2015 and integrated them into a salvage and modernization program, with older P-21 Styx II missiles among the likely pre-existing anti-ship missiles in the Yemeni arsenal.
By 2022, the Rubezh was visible in Houthi public messaging rather than confirmed in a documented strike. The UN Panel placed the Rubezh display at the 1 September 2022 Hudaydah parade, and later CTC analysis noted that older Rubezh B-21/B-22 anti-ship cruise missiles had been de-prioritized into parade floats, emergency stores, spare parts, or decoys as newer anti-ship systems took priority.
Sources: CTC Houthi War Machine, UN Panel Yemen 2023 Final Report, CTC Houthi War Effort
Use pattern
The documented user was Houthi-aligned forces. The role was coastal area denial and captured anti-ship missile stockholding: the system was part of the missile inventory threatening Red Sea and Bab el-Mandeb traffic, but the public evidence separates possession and display from a traced Rubezh launch.
This distinction matters because Houthi anti-shipping activity in Yemen involved several weapon families. CTC and The War Zone both describe older P-21/P-22 or Rubezh-family weapons alongside C-801/Al-Mandab and later Iranian-linked systems, while the UN Panel treated the displayed Rubezh/P-15 as a less sophisticated system whose operational status could not be confirmed from the parade.
The available sources therefore support a published conflict-use page for captured and fielded coastal-defense materiel in the Yemen war, not a claim that a 4K51 launcher fired a specific combat shot. Later Red Sea attacks are better supported at the class or newer-system level unless a source identifies the Rubezh/P-21/P-22 family in a particular incident.
Sources: CTC Houthi War Machine, TWZ Houthi Anti-Ship Arsenal, UN Panel Yemen 2023 Final Report, CTC Houthi War Effort
