diff --git a/pmb/core/arch.py b/pmb/core/arch.py
index 237cdcce..409e8df8 100644
--- a/pmb/core/arch.py
+++ b/pmb/core/arch.py
@@ -61,6 +61,8 @@ class Arch(enum.Enum):
                 return Arch.armhf
             case "armv7l" | "armv8l":
                 return Arch.armv7
+            case _:
+                raise ValueError(f"Unsupported machine type '{machine_type}'")
 
     @staticmethod
     def native() -> "Arch":
diff --git a/pmb/core/test_arch.py b/pmb/core/test_arch.py
index 7598eab5..a91a6130 100644
--- a/pmb/core/test_arch.py
+++ b/pmb/core/test_arch.py
@@ -77,3 +77,7 @@ def test_invalid_arches():
     with pytest.raises(TypeError) as excinfo:
         "bap" / Arch.aarch64
     assert "unsupported operand type(s) for /: 'str' and 'Arch'" in str(excinfo.value)
+
+    with pytest.raises(ValueError) as excinfo:
+        Arch.from_machine_type("invalid")
+    assert "Unsupported machine type 'invalid'" in str(excinfo.value)