diff --git a/cypress/e2e/vault.cy.js b/cypress/e2e/vault.cy.js
--- a/cypress/e2e/vault.cy.js
+++ b/cypress/e2e/vault.cy.js
@@ -118,6 +118,25 @@
 
   });
 
+  it('should report pending cooking task when already submitted', function() {
+    // Browse a directory
+    cy.visit(this.directoryUrl);
+
+    // Stub responses when requesting the vault API to simulate
+    // an internal server error
+    cy.intercept(this.vaultDirectoryUrl, {
+      body: this.genVaultDirCookingResponse('pending', 'Processing...')
+    }).as('checkVaultCookingTask');
+
+    cy.contains('button', 'Download')
+      .click();
+
+    // Check error alert is displayed
+    cy.get('.alert-success')
+    .should('be.visible')
+    .should('contain', 'Archive cooking request already submitted');
+  });
+
   it('should report an error when vault service is experiencing issues', function() {
     // Browse a directory
     cy.visit(this.directoryUrl);
diff --git a/swh/web/vault/assets/vault-create-tasks.js b/swh/web/vault/assets/vault-create-tasks.js
--- a/swh/web/vault/assets/vault-create-tasks.js
+++ b/swh/web/vault/assets/vault-create-tasks.js
@@ -48,7 +48,16 @@
     const vaultModalId = `#vault-fetch-${objectType}-modal`;
     $(vaultModalId).modal('show');
     $('body').on('keyup', vaultModalId, vaultModalHandleEnterKey);
-  } else {
+  } else if (data.status === 'pending') {
+    const cookingInProgressAlert =
+      $(htmlAlert('success',
+                  'Archive cooking request already submitted.<br/>' +
+                  `Go to the <a href="${Urls.vault()}">Downloads</a> page ` +
+                  'to get the download link once it is ready.',
+                  true));
+    cookingInProgressAlert.css(alertStyle);
+    $('body').append(cookingInProgressAlert);
+  } else if (!response.ok) {
     const cookingServiceDownAlert =
           $(htmlAlert('danger',
                       'Archive cooking service is currently experiencing issues.<br/>' +