That breakdown led many fans to expect that the spin-off would eventually stream on Disney+ internationally . . .

Although Disney+ has never publicly announced a firm release date for the spin-off, an earlier BBC press release reportedly said that The War Between the Land and the Sea would stream on Disney+ in early 2026.
With June now here and no listing on the service, that window appears to have passed.
At this stage, there has been no official explanation from Disney+ about the delay.
The lack of a release date has led to fresh questions over whether anything has changed in the BBC and Disney+ arrangement for Doctor Who and its related projects. It is not yet clear whether the streamer still plans to carry the series internationally.

The situation is made more interesting by the fact that, in the United States, Doctor Who Series 1 to 13 (2005–2022) is set to stream on AMC+ from June.
That move highlights how Doctor Who streaming rights are now split across different platforms depending on the era and region, which may be adding to confusion for viewers.
For now, UK viewers can watch The War Between the Land and the Sea on BBC iPlayer.
Fans outside the UK who want to see the series can also import the DVD or Blu-ray from UK retailers, although international buyers should remember that the Blu-ray release requires Region B-compatible hardware.

As things stand, The War Between the Land and the Sea has still not been added to Disney+, despite earlier expectations of an early 2026 debut.
Until Disney+ or the BBC provides an update, the international streaming future of the Doctor Who spin-off remains uncertain.