diff --git a/README.md b/README.md
index e51cfe5..d62ade6 100644
--- a/README.md
+++ b/README.md
@@ -16,6 +16,8 @@ Interface for using cupy in xarray, providing convenience accessors.
 
 ## Installation
 
+> `cupy-xarray` will use an existing cupy installation, hence cupy needs to be installed manually! Please follow cupy's install instructions at <https://docs.cupy.dev/en/stable/install.html>.
+
 From anaconda:
 
 ```console
diff --git a/cupy_xarray/accessors.py b/cupy_xarray/accessors.py
index 3f828bb..b26ee58 100644
--- a/cupy_xarray/accessors.py
+++ b/cupy_xarray/accessors.py
@@ -1,6 +1,16 @@
+import warnings
 from typing import TYPE_CHECKING, Any
 
-import cupy as cp
+try:
+    import cupy as cp
+except ImportError as e:
+    warnings.warn(
+        "Cupy is not installed. cupy-xarray expects cupy to be manually installed. Please install "
+        "cupy by following the instructions at https://docs.cupy.dev/en/stable/install.html.",
+        ImportWarning,
+        stacklevel=2,
+    )
+    raise e
 from xarray import (
     DataArray,
     Dataset,
diff --git a/docs/index.md b/docs/index.md
index fdea96c..56f1995 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -16,6 +16,8 @@ CuPy-Xarray is a Python library that leverages [CuPy](https://cupy.dev/), a GPU
 
 ## Installation
 
+> `cupy-xarray` will use an existing cupy installation, hence cupy needs to be installed manually! Please follow cupy's install instructions at <https://docs.cupy.dev/en/stable/install.html>.
+
 CuPy-Xarray can be installed using `pip` or `conda`:
 
 From Conda Forge:
diff --git a/pyproject.toml b/pyproject.toml
index be870da..d98b3fe 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -15,7 +15,6 @@ classifiers = [
 ]
 dynamic = ["version"]
 dependencies = [
-    "cupy",
     "xarray>=2024.02.0",
 ]