diff --git a/.zenodo.json b/.zenodo.json
index 1058e3b15..29e7f047a 100644
--- a/.zenodo.json
+++ b/.zenodo.json
@@ -558,7 +558,7 @@
       "name": "Flandin, Guillaume"
     },
     {
-      "affiliation": "Stereotaxy Core, Brain & Spine Institute",
+      "affiliation": "University College London",
       "name": "P\u00e9rez-Garc\u00eda, Fernando",
       "orcid": "0000-0001-9090-3024"
     },
diff --git a/nipype/interfaces/niftyreg/regutils.py b/nipype/interfaces/niftyreg/regutils.py
index 7c3ed28ea..0910b7d65 100644
--- a/nipype/interfaces/niftyreg/regutils.py
+++ b/nipype/interfaces/niftyreg/regutils.py
@@ -122,7 +122,7 @@ warpfield.nii -res im2_res.nii.gz'
     # Need this overload to properly constraint the interpolation type input
     def _format_arg(self, name, spec, value):
         if name == 'inter_val':
-            inter_val = {'NN': 0, 'LIN': 1, 'CUB': 3, 'SINC': 5}
+            inter_val = {'NN': 0, 'LIN': 1, 'CUB': 3, 'SINC': 4}
             return spec.argstr % inter_val[value]
         else:
             return super(RegResample, self)._format_arg(name, spec, value)
@@ -295,6 +295,15 @@ class RegToolsInputSpec(NiftyRegCommandInputSpec):
         desc=desc,
         argstr='-smoG %f %f %f')
 
+    # Interpolation type
+    inter_val = traits.Enum(
+        'NN',
+        'LIN',
+        'CUB',
+        'SINC',
+        desc='Interpolation order to use to warp the floating image',
+        argstr='-interp %d')
+
 
 class RegToolsOutputSpec(TraitedSpec):
     """ Output Spec for RegTools. """
@@ -326,6 +335,14 @@ class RegTools(NiftyRegCommand):
     output_spec = RegToolsOutputSpec
     _suffix = '_tools'
 
+    # Need this overload to properly constraint the interpolation type input
+    def _format_arg(self, name, spec, value):
+        if name == 'inter_val':
+            inter_val = {'NN': 0, 'LIN': 1, 'CUB': 3, 'SINC': 4}
+            return spec.argstr % inter_val[value]
+        else:
+            return super(RegTools, self)._format_arg(name, spec, value)
+
 
 class RegAverageInputSpec(NiftyRegCommandInputSpec):
     """ Input Spec for RegAverage. """

NiftyReg's RegTools is missing interpolation order argument
diff --git a/nipype/interfaces/niftyreg/tests/test_auto_RegTools.py b/nipype/interfaces/niftyreg/tests/test_auto_RegTools.py
index 97ea5e6c9..f0f66083c 100644
--- a/nipype/interfaces/niftyreg/tests/test_auto_RegTools.py
+++ b/nipype/interfaces/niftyreg/tests/test_auto_RegTools.py
@@ -24,6 +24,7 @@ def test_RegTools_inputs():
             argstr='-in %s',
             mandatory=True,
         ),
+        inter_val=dict(argstr='-interp %d', ),
         iso_flag=dict(argstr='-iso', ),
         mask_file=dict(argstr='-nan %s', ),
         mul_val=dict(argstr='-mul %s', ),

pip install -e .[dev]
parse_log_pytest
requirements.txt
pytest
apt-get update apt-get install -y gcc
3.6
requirements.txt
pytest --no-header -rA --tb=line --color=no -p no:cacheprovider -W ignore::DeprecationWarning
attrs==22.2.0
certifi==2021.5.30
click==8.0.4
configparser==5.2.0
decorator==4.4.2
funcsigs==1.0.2
future==1.0.0
importlib-metadata==4.8.3
iniconfig==1.1.1
isodate==0.6.1
lxml==5.3.1
mock==5.2.0
networkx==2.5.1
nibabel==3.2.2
-e git+https://github.com/nipy/nipype.git@6ca791d9c5ec0efb9f56cc9e44758d6e53ffb800#egg=nipype
numpy==1.19.5
packaging==21.3
pluggy==1.0.0
prov==1.5.0
py==1.11.0
pydot==1.4.2
pydotplus==2.0.2
pyparsing==3.1.4
pytest==7.0.1
python-dateutil==2.9.0.post0
rdflib==5.0.0
scipy==1.5.4
simplejson==3.20.1
six==1.17.0
tomli==1.2.3
traits==6.4.1
typing_extensions==4.1.1
zipp==3.6.0

name: nipype
channels:
  - defaults
  - https://repo.anaconda.com/pkgs/main
  - https://repo.anaconda.com/pkgs/r
  - conda-forge
dependencies:
  - _libgcc_mutex=0.1=main
  - _openmp_mutex=5.1=1_gnu
  - ca-certificates=2025.2.25=h06a4308_0
  - certifi=2021.5.30=py36h06a4308_0
  - ld_impl_linux-64=2.40=h12ee557_0
  - libffi=3.3=he6710b0_2
  - libgcc-ng=11.2.0=h1234567_1
  - libgomp=11.2.0=h1234567_1
  - libstdcxx-ng=11.2.0=h1234567_1
  - ncurses=6.4=h6a678d5_0
  - openssl=1.1.1w=h7f8727e_0
  - pip=21.2.2=py36h06a4308_0
  - python=3.6.13=h12debd9_1
  - readline=8.2=h5eee18b_0
  - setuptools=58.0.4=py36h06a4308_0
  - sqlite=3.45.3=h5eee18b_0
  - tk=8.6.14=h39e8969_0
  - wheel=0.37.1=pyhd3eb1b0_0
  - xz=5.6.4=h5eee18b_1
  - zlib=1.2.13=h5eee18b_1
  - pip:
      - attrs==22.2.0
      - click==8.0.4
      - configparser==5.2.0
      - decorator==4.4.2
      - funcsigs==1.0.2
      - future==1.0.0
      - importlib-metadata==4.8.3
      - iniconfig==1.1.1
      - isodate==0.6.1
      - lxml==5.3.1
      - mock==5.2.0
      - networkx==2.5.1
      - nibabel==3.2.2
      - numpy==1.19.5
      - packaging==21.3
      - pluggy==1.0.0
      - prov==1.5.0
      - py==1.11.0
      - pydot==1.4.2
      - pydotplus==2.0.2
      - pyparsing==3.1.4
      - pytest==7.0.1
      - python-dateutil==2.9.0.post0
      - rdflib==5.0.0
      - scipy==1.5.4
      - simplejson==3.20.1
      - six==1.17.0
      - tomli==1.2.3
      - traits==6.4.1
      - typing-extensions==4.1.1
      - zipp==3.6.0
prefix: /opt/conda/envs/nipype

nipype/interfaces/niftyreg/tests/test_auto_RegTools.py::test_RegTools_inputs
nipype/interfaces/niftyreg/tests/test_auto_RegTools.py::test_RegTools_outputs
nipype/interfaces/niftyreg/regutils.py .zenodo.json
nipype/interfaces/niftyreg/regutils.py .zenodo.json