diff --git a/app/components/contribution-list/template.hbs b/app/components/contribution-list/template.hbs
index d6495a6..f806246 100644
--- a/app/components/contribution-list/template.hbs
+++ b/app/components/contribution-list/template.hbs
@@ -33,7 +33,7 @@
   {{#each contributionsFiltered as |contribution|}}
     <li role="button" {{action "openContributionDetails" contribution}}
         data-contribution-id={{contribution.id}}
-        class="{{contribution-status contribution}}{{if contribution.vetoed " vetoed"}}{{if (eq contribution.id selectedContributionId) " selected"}}">
+        class="{{contribution-status contribution}}{{if contribution.hasPendingChanges " pending"}}{{if contribution.vetoed " vetoed"}}{{if (eq contribution.id selectedContributionId) " selected"}}">
       <p class="meta">
         <span class="recipient">{{user-avatar contributor=contribution.contributor}}</span>
         <span class="category {{contribution.kind}}">({{contribution.kind}})</span>
@@ -45,7 +45,10 @@
       {{#unless contribution.vetoed}}
         {{#unless (is-confirmed-contribution contribution)}}
           <p class="voting">
-            <button {{action "veto" contribution.id}} class="small danger">veto</button>
+            {{input type="button" class="button small danger"
+                    click=(action "veto" contribution.id)
+                    disabled=contribution.hasPendingChanges
+                    value="veto"}}
           </p>
         {{/unless}}
       {{/unless}}
diff --git a/app/models/contribution.js b/app/models/contribution.js
index c6985fa..1b89125 100644
--- a/app/models/contribution.js
+++ b/app/models/contribution.js
@@ -1,5 +1,5 @@
 import EmberObject, { computed } from '@ember/object';
-import { isEmpty } from '@ember/utils';
+import { isEmpty, isPresent } from '@ember/utils';
 import bignumber from 'kredits-web/utils/cps/bignumber';
 import moment from 'moment';
 
@@ -24,6 +24,8 @@ export default EmberObject.extend({
   time: null,
   ipfsData: '',
 
+  pendingTx: null,
+
   init () {
     this._super(...arguments);
     if (isEmpty(this.details)) this.set('details', {});
@@ -35,6 +37,10 @@ export default EmberObject.extend({
 
   jsDate: computed('iso8601Date', function() {
     return moment(this.iso8601Date).toDate();
+  }),
+
+  hasPendingChanges: computed('pendingTx', function() {
+    return isPresent(this.pendingTx);
   })
 
 });
diff --git a/app/services/kredits.js b/app/services/kredits.js
index 3fc96d3..30e3eb4 100644
--- a/app/services/kredits.js
+++ b/app/services/kredits.js
@@ -225,6 +225,7 @@ export default Service.extend({
         console.debug('[kredits] add contribution response', data);
         attributes.contributor = this.contributors.findBy('id', attributes.contributorId);
         const contribution = Contribution.create(attributes);
+        contribution.set('pendingTx', data);
         contribution.set('confirmedAtBlock', data.blockNumber + 40320);
         this.contributions.pushObject(contribution);
         return contribution;
@@ -278,10 +279,12 @@ export default Service.extend({
 
   veto (contributionId) {
     console.debug('[kredits] veto against', contributionId);
+    const contribution = this.contributions.findBy('id', contributionId);
 
     return this.kredits.Contribution.functions.veto(contributionId, { gasLimit: 300000 })
       .then(data => {
         console.debug('[kredits] veto response', data);
+        contribution.set('pendingTx', data);
         return data;
       });
   },
@@ -367,6 +370,7 @@ export default Service.extend({
 
     if (contribution) {
       contribution.set('vetoed', true);
+      contribution.set('pendingTx', null);
     }
   },
 
diff --git a/tests/unit/models/contribution-test.js b/tests/unit/models/contribution-test.js
index 4dc28a1..9ab6905 100644
--- a/tests/unit/models/contribution-test.js
+++ b/tests/unit/models/contribution-test.js
@@ -24,4 +24,13 @@ module('Unit | Model | contribution', function(hooks) {
     assert.ok(model.jsDate instanceof Date);
     assert.equal(model.jsDate.toISOString(), '2019-09-10T09:33:00.141Z');
   });
+
+  test('hasPendingChanges', function(assert) {
+    const model = Contribution.create({});
+    assert.equal(model.hasPendingChanges, false);
+
+    model.set('pendingTx', { hash: 'abcdef123456' });
+    assert.equal(model.hasPendingChanges, true);
+  });
+
 });