Corollary 1
Tag 01CE, permanent. Cite it as [Bourbaki, Tag 01CE].
Lie Groups and Lie Algebras, chapter IX, § 4. Root system associated to a compact group
There are only finitely-many closed subgroups of G containing T.
Let H be such a subgroup; then , and is finite. Moreover, H is a subgroup of containing , and is finite (§2, no. 4, Prop. 4 and Remark 2).
Bourbaki sets the proof directly after the statement, and the corpus does not separate them, so what is above is the statement and its proof together.