diff --git a/src/proj/EPSG_2056.js b/src/proj/EPSG_2056.js
index 829832448026..b156920c2cd8 100644
--- a/src/proj/EPSG_2056.js
+++ b/src/proj/EPSG_2056.js
@@ -19,7 +19,7 @@
 // IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 // CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-import create from 'ngeo/proj/utils';
+import {createProjection} from 'ngeo/proj/utils';
 
 export const code = 'EPSG:2056';
 
@@ -37,8 +37,7 @@ const def = [
 ];
 const extent = [2420000, 1030000, 2900000, 1350000];
 
-const projections = {};
-projections[code] = {'definition': def, 'extent': extent};
-export const proj = create(projections);
+const projection = {'definition': def, 'extent': extent};
+export const proj = createProjection(code, projection);
 
 export default code;
diff --git a/src/proj/EPSG_21781.js b/src/proj/EPSG_21781.js
index c68faf9f0dd5..f58a0c77f5ed 100644
--- a/src/proj/EPSG_21781.js
+++ b/src/proj/EPSG_21781.js
@@ -19,7 +19,7 @@
 // IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 // CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-import create from 'ngeo/proj/utils';
+import {createProjection} from 'ngeo/proj/utils';
 
 export const code = 'EPSG:21781';
 
@@ -37,8 +37,7 @@ const def = [
 ];
 const extent = [420000, 30000, 900000, 350000];
 
-const projections = {};
-projections[code] = {'definition': def, 'extent': extent};
-export const proj = create(projections);
+const projection = {'definition': def, 'extent': extent};
+export const proj = createProjection(code, projection);
 
 export default code;
diff --git a/src/proj/utils.js b/src/proj/utils.js
index 5415fadb31b2..99d0226fc860 100644
--- a/src/proj/utils.js
+++ b/src/proj/utils.js
@@ -19,25 +19,33 @@
 // IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 // CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-import {get as getProjection, add as addProjection} from 'ol/proj';
+import {get as getProjection} from 'ol/proj';
 import {register} from 'ol/proj/proj4';
 import proj4 from 'proj4';
 
-/** @type {import('gmf/options').gmfProjectionsOptions} */
-export default function createProjections(projections) {
-  for (const code in projections) {
-    proj4.defs(code, projections[code].definition.join(' ').trim());
-    const match = /^EPSG:(\d+)$/.exec(code);
-    if (match !== null) {
-      proj4.defs(
-        'http://www.opengis.net/gml/srs/epsg.xml#' + match[1], //NOSONAR
-        proj4.defs(code),
-      );
-    }
+/**
+ * @type {string} the projection code.
+ * @type {import('gmf/options').Projection} the projection settings.
+ * @returns {import('ol/proj/Projection').default} the registered projection.
+ */
+export function createProjection(code, projection) {
+  proj4.defs(code, projection.definition.join(' ').trim());
+  const match = /^EPSG:(\d+)$/.exec(code);
+  if (match !== null) {
+    proj4.defs(
+      'http://www.opengis.net/gml/srs/epsg.xml#' + match[1], //NOSONAR
+      proj4.defs(code),
+    );
   }
   register(proj4);
+  const proj = getProjection(code);
+  proj.setExtent(projection.extent);
+  return proj;
+}
+
+/** @type {import('gmf/options').gmfProjectionsOptions} */
+export default function createProjections(projections) {
   for (const code in projections) {
-    const proj = getProjection(code);
-    proj.setExtent(projections[code].extent);
+    createProjection(code, projections[code]);
   }
 }