diff --git a/poetry.lock b/poetry.lock
index 911cda7bf..c9d17702b 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -1767,14 +1767,14 @@ test = ["pytest (>=7.2)", "pytest-cov (>=4.0)"]
 
 [[package]]
 name = "nltk"
-version = "3.8.1"
+version = "3.9.1"
 description = "Natural Language Toolkit"
 optional = false
-python-versions = ">=3.7"
+python-versions = ">=3.8"
 groups = ["dev"]
 files = [
-    {file = "nltk-3.8.1-py3-none-any.whl", hash = "sha256:fd5c9109f976fa86bcadba8f91e47f5e9293bd034474752e92a520f81c93dda5"},
-    {file = "nltk-3.8.1.zip", hash = "sha256:1834da3d0682cba4f2cede2f9aad6b0fafb6461ba451db0efb6f9c39798d64d3"},
+    {file = "nltk-3.9.1-py3-none-any.whl", hash = "sha256:4fa26829c5b00715afe3061398a8989dc643b92ce7dd93fb4585a70930d168a1"},
+    {file = "nltk-3.9.1.tar.gz", hash = "sha256:87d127bd3de4bd89a4f81265e5fa59cb1b199b27440175370f7417d2bc7ae868"},
 ]
 
 [package.dependencies]
@@ -3586,4 +3586,4 @@ test = ["big-O", "importlib-resources ; python_version < \"3.9\"", "jaraco.funct
 [metadata]
 lock-version = "2.1"
 python-versions = "^3.9"
-content-hash = "360e7128e1296a81a16070db02a7145bf9e807f3795bcfe56f4e1e453c976f6b"
+content-hash = "84243d0376dded1435e1defadde55a26a8d2b1428792e307c8db139721262fe6"
diff --git a/pyproject.toml b/pyproject.toml
index 9af0c843c..bb3bba8e8 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -41,7 +41,7 @@ tabulate = "^0.9"
 # for TokenClassificationModelWithSeq2SeqEncoderAndCrf
 pytorch-crf = ">=0.7.2"
 # for rouge metric (tests only) and for NltkSentenceSplitter
-nltk = "^3.8.1"
+nltk = "^3.9.1"
 # for NltkSentenceSplitter
 flair = "^0.13.1"
 # for SpansViaRelationMerger
diff --git a/src/pie_modules/document/processing/sentence_splitter.py b/src/pie_modules/document/processing/sentence_splitter.py
index 5230e2d19..ac28b94a9 100644
--- a/src/pie_modules/document/processing/sentence_splitter.py
+++ b/src/pie_modules/document/processing/sentence_splitter.py
@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import logging
+import os
 from typing import TypeVar
 
 from pie_modules.annotations import LabeledSpan
@@ -30,8 +31,9 @@ def __init__(
         self,
         partition_layer_name: str = "labeled_partitions",
         text_field_name: str = "text",
-        sentencizer_url: str = "tokenizers/punkt/PY3/english.pickle",
+        language: str = "english",
         inplace: bool = True,
+        sentencizer_url: str | None = None,
     ):
         try:
             import nltk
@@ -41,12 +43,19 @@ def __init__(
                 "You can install NLTK with `pip install nltk`."
             )
 
+        if sentencizer_url is not None:
+            logger.warning(
+                "The 'sentencizer_url' argument is deprecated. Please use 'language' instead."
+            )
+            if sentencizer_url[-7:] == ".pickle":
+                language = os.path.split(sentencizer_url[:-7])[-1]
+
         self.partition_layer_name = partition_layer_name
         self.text_field_name = text_field_name
         self.inplace = inplace
         # download the NLTK Punkt tokenizer model
-        nltk.download("punkt")
-        self.sentencizer = nltk.data.load(sentencizer_url)
+        nltk.download("punkt_tab")
+        self.sentencizer = nltk.tokenize.PunktTokenizer(language)
 
     def __call__(self, document: D) -> D:
         if not self.inplace:
diff --git a/tests/document/processing/test_sentence_splitter.py b/tests/document/processing/test_sentence_splitter.py
index 590670bc5..a64fadf02 100644
--- a/tests/document/processing/test_sentence_splitter.py
+++ b/tests/document/processing/test_sentence_splitter.py
@@ -37,6 +37,35 @@ def test_nltk_sentence_splitter(caplog, inplace):
     assert str(doc.labeled_partitions[1]) == "This is another one."
 
 
+def test_nltk_sentence_splitter_deprecated_arg(caplog):
+    doc = TextDocumentWithLabeledPartitions(
+        text="This is a test sentence. This is another one.", id="test_doc"
+    )
+    # add a dummy text partition to trigger the warning (see below)
+    doc.labeled_partitions.append(LabeledSpan(start=0, end=len(doc.text), label="text"))
+    caplog.clear()
+    # create the sentence splitter
+    with caplog.at_level("WARNING"):
+        sentence_splitter = NltkSentenceSplitter(
+            inplace=True, sentencizer_url="tokenizers/punkt/PY3/english.pickle"
+        )
+    # call the sentence splitter
+    result = sentence_splitter(doc)
+
+    assert result is doc
+    # check the log messages
+    assert len(caplog.records) == 2
+    assert caplog.messages == [
+        "The 'sentencizer_url' argument is deprecated. Please use 'language' instead.",
+        "Layer labeled_partitions in document test_doc is not empty. "
+        "Clearing it before adding new sentence partitions.",
+    ]
+    # check the result
+    assert len(doc.labeled_partitions) == 2
+    assert str(doc.labeled_partitions[0]) == "This is a test sentence."
+    assert str(doc.labeled_partitions[1]) == "This is another one."
+
+
 @pytest.mark.parametrize("inplace", [True, False])
 def test_flair_segtok_sentence_splitter(caplog, inplace):
     doc = TextDocumentWithLabeledPartitions(