diff --git a/src/parcels/_core/fieldset.py b/src/parcels/_core/fieldset.py
index 11a1b86ca..9f8ecb8b2 100644
--- a/src/parcels/_core/fieldset.py
+++ b/src/parcels/_core/fieldset.py
@@ -263,7 +263,7 @@ def from_ugrid_conventions(
         -----
         See https://ugrid-conventions.github.io/ugrid-conventions/ for more information on the UGRID conventions.
         """
-        model = UnstructuredModelData.from_ugrid_conventions(ds, mesh, vector_fields)
+        model = UnstructuredModelData.from_ugrid_conventions(ds, mesh=mesh, vector_fields=vector_fields)
         return cls([model])
 
     @classmethod
@@ -308,7 +308,7 @@ def from_sgrid_conventions(
         See https://sgrid.github.io/sgrid/ for more information on the SGRID conventions.
         """
         model = StructuredModelData.from_sgrid_conventions(
-            ds, mesh, vector_fields, skip_field_data_validation=skip_field_data_validation
+            ds, mesh=mesh, vector_fields=vector_fields, skip_field_data_validation=skip_field_data_validation
         )
         return cls([model])
 
diff --git a/src/parcels/_core/model.py b/src/parcels/_core/model.py
index 270723a97..848bf2fd2 100644
--- a/src/parcels/_core/model.py
+++ b/src/parcels/_core/model.py
@@ -203,6 +203,7 @@ def construct_fields(self) -> list[Field | VectorField]:
     def from_sgrid_conventions(
         cls,
         ds: xr.Dataset,
+        *,
         mesh: ptyping.TMesh | None,
         vector_fields: ptyping.VectorFields | NotSetType,
         skip_field_data_validation: bool = False,
@@ -358,7 +359,7 @@ def scalar_field_names(self) -> list[str]:
 
     @classmethod
     def from_ugrid_conventions(
-        cls, ds: ux.UxDataset, mesh: ptyping.TMesh, vector_fields: ptyping.VectorFields | NotSetType
+        cls, ds: ux.UxDataset, *, mesh: ptyping.TMesh, vector_fields: ptyping.VectorFields | NotSetType
     ):
         ds_dims = list(ds.dims)
         if not all(dim in ds_dims for dim in ["time", "zf", "zc"]):
diff --git a/src/parcels/_core/particleset.py b/src/parcels/_core/particleset.py
index 3b5ecf2aa..fb77851f4 100644
--- a/src/parcels/_core/particleset.py
+++ b/src/parcels/_core/particleset.py
@@ -60,6 +60,7 @@ def __init__(
         self,
         fieldset,
         pclass=Particle,
+        *,
         t=None,
         z=None,
         y=None,