diff --git a/bin/pungi-koji b/bin/pungi-koji
index 359d4373..c7e50ff6 100755
--- a/bin/pungi-koji
+++ b/bin/pungi-koji
@@ -212,6 +212,7 @@ def run_compose(compose):
     createiso_phase = pungi.phases.CreateisoPhase(compose)
     liveimages_phase = pungi.phases.LiveImagesPhase(compose)
     image_build_phase = pungi.phases.ImageBuildPhase(compose)
+    image_checksum_phase = pungi.phases.ImageChecksumPhase(compose)
     test_phase = pungi.phases.TestPhase(compose)
 
     # check if all config options are set
@@ -219,7 +220,7 @@ def run_compose(compose):
     for phase in (init_phase, pkgset_phase, createrepo_phase,
                   buildinstall_phase, productimg_phase, gather_phase,
                   extrafiles_phase, createiso_phase, liveimages_phase,
-                  image_build_phase, test_phase):
+                  image_build_phase, image_checksum_phase, test_phase):
         if phase.skip():
             continue
         try:
@@ -289,19 +290,8 @@ def run_compose(compose):
     liveimages_phase.stop()
     image_build_phase.stop()
 
-    # merge checksum files
-    for variant in compose.get_variants(types=["variant", "layered-product"]):
-        for arch in variant.arches + ["src"]:
-            iso_dir = compose.paths.compose.iso_dir(arch, variant, create_dir=False)
-            if not iso_dir or not os.path.exists(iso_dir):
-                continue
-            for checksum_type in ("md5", "sha1", "sha256"):
-                checksum_upper = "%sSUM" % checksum_type.upper()
-                checksums = sorted([i for i in os.listdir(iso_dir) if i.endswith(".%s" % checksum_upper)])
-                fo = open(os.path.join(iso_dir, checksum_upper), "w")
-                for i in checksums:
-                    data = open(os.path.join(iso_dir, i), "r").read()
-                    fo.write(data)
+    image_checksum_phase.start()
+    image_checksum_phase.stop()
 
     pungi.metadata.write_compose_info(compose)
     compose.im.dump(compose.paths.compose.metadata("images.json"))
diff --git a/pungi/phases/__init__.py b/pungi/phases/__init__.py
index c3be00cd..81e319d9 100644
--- a/pungi/phases/__init__.py
+++ b/pungi/phases/__init__.py
@@ -27,3 +27,4 @@ from createiso import CreateisoPhase  # noqa
 from live_images import LiveImagesPhase  # noqa
 from image_build import ImageBuildPhase  # noqa
 from test import TestPhase  # noqa
+from image_checksum import ImageChecksumPhase    # noqa
diff --git a/pungi/phases/image_checksum.py b/pungi/phases/image_checksum.py
new file mode 100644
index 00000000..e9c0df9e
--- /dev/null
+++ b/pungi/phases/image_checksum.py
@@ -0,0 +1,30 @@
+# -*- coding: utf-8 -*-
+
+import os
+
+from .base import PhaseBase
+
+
+class ImageChecksumPhase(PhaseBase):
+    """Go through images generated in ImageBuild phase and generate their
+    checksums.
+    """
+
+    name = 'image_checksum'
+
+    def run(self):
+        compose = self.compose
+        # merge checksum files
+        for variant in compose.get_variants(types=["variant", "layered-product"]):
+            for arch in variant.arches + ["src"]:
+                iso_dir = compose.paths.compose.iso_dir(arch, variant, create_dir=False)
+                if not iso_dir or not os.path.exists(iso_dir):
+                    continue
+                for checksum_type in ("md5", "sha1", "sha256"):
+                    checksum_upper = "%sSUM" % checksum_type.upper()
+                    checksums = sorted([i for i in os.listdir(iso_dir) if i.endswith(".%s" % checksum_upper)])
+                    fo = open(os.path.join(iso_dir, checksum_upper), "w")
+                    for i in checksums:
+                        data = open(os.path.join(iso_dir, i), "r").read()
+                        fo.write(data)
+                    fo.close()