diff --git a/kallithea/config/routing.py b/kallithea/config/routing.py
--- a/kallithea/config/routing.py
+++ b/kallithea/config/routing.py
@@ -573,7 +573,7 @@ def make_map(config):
 
     rmap.connect("edit_repo_advanced_fork", "/{repo_name:.*?}/settings/advanced/fork",
                  controller='admin/repos', action="edit_advanced_fork",
-                 conditions=dict(method=["PUT"], function=check_repo))
+                 conditions=dict(method=["POST"], function=check_repo))
 
 
     rmap.connect("edit_repo_caches", "/{repo_name:.*?}/settings/caches",
diff --git a/kallithea/templates/admin/repos/repo_edit_advanced.html b/kallithea/templates/admin/repos/repo_edit_advanced.html
--- a/kallithea/templates/admin/repos/repo_edit_advanced.html
+++ b/kallithea/templates/admin/repos/repo_edit_advanced.html
@@ -1,5 +1,5 @@
 <h3>${_('Parent')}</h3>
-${h.form(url('edit_repo_advanced_fork', repo_name=c.repo_info.repo_name), method='put')}
+${h.form(url('edit_repo_advanced_fork', repo_name=c.repo_info.repo_name))}
 <div class="form">
        ${h.select('id_fork_of','',c.repos_list,class_="medium")}
        ${h.submit('set_as_fork_%s' % c.repo_info.repo_name,_('Set'),class_="btn btn-small")}
diff --git a/kallithea/tests/functional/test_admin_repos.py b/kallithea/tests/functional/test_admin_repos.py
--- a/kallithea/tests/functional/test_admin_repos.py
+++ b/kallithea/tests/functional/test_admin_repos.py
@@ -492,7 +492,7 @@ class _BaseTestCase(TestController):
         fixture.create_repo(other_repo, repo_type=self.REPO_TYPE)
         repo = Repository.get_by_repo_name(self.REPO)
         repo2 = Repository.get_by_repo_name(other_repo)
-        response = self.app.put(url('edit_repo_advanced_fork', repo_name=self.REPO),
+        response = self.app.post(url('edit_repo_advanced_fork', repo_name=self.REPO),
                                 params=dict(id_fork_of=repo2.repo_id, _authentication_token=self.authentication_token()))
         repo = Repository.get_by_repo_name(self.REPO)
         repo2 = Repository.get_by_repo_name(other_repo)
@@ -513,7 +513,7 @@ class _BaseTestCase(TestController):
         self.log_user()
         repo = Repository.get_by_repo_name(self.REPO)
         repo2 = Repository.get_by_repo_name(self.OTHER_TYPE_REPO)
-        response = self.app.put(url('edit_repo_advanced_fork', repo_name=self.REPO),
+        response = self.app.post(url('edit_repo_advanced_fork', repo_name=self.REPO),
                                 params=dict(id_fork_of=repo2.repo_id, _authentication_token=self.authentication_token()))
         repo = Repository.get_by_repo_name(self.REPO)
         repo2 = Repository.get_by_repo_name(self.OTHER_TYPE_REPO)
@@ -523,7 +523,7 @@ class _BaseTestCase(TestController):
     def test_set_fork_of_none(self):
         self.log_user()
         ## mark it as None
-        response = self.app.put(url('edit_repo_advanced_fork', repo_name=self.REPO),
+        response = self.app.post(url('edit_repo_advanced_fork', repo_name=self.REPO),
                                 params=dict(id_fork_of=None, _authentication_token=self.authentication_token()))
         repo = Repository.get_by_repo_name(self.REPO)
         repo2 = Repository.get_by_repo_name(self.OTHER_TYPE_REPO)
@@ -535,7 +535,7 @@ class _BaseTestCase(TestController):
     def test_set_fork_of_same_repo(self):
         self.log_user()
         repo = Repository.get_by_repo_name(self.REPO)
-        response = self.app.put(url('edit_repo_advanced_fork', repo_name=self.REPO),
+        response = self.app.post(url('edit_repo_advanced_fork', repo_name=self.REPO),
                                 params=dict(id_fork_of=repo.repo_id, _authentication_token=self.authentication_token()))
         self.checkSessionFlash(response,
                                'An error occurred during this operation')