Wpf Storyboard остановить анимацию

У меня есть стиль с анимацией по клику button, анимация должна работать не известное количество времени, подскажите как я могу остановить её когда это нужно будет.

<Style x:Key="ButtonStyleWidthUpload" TargetType="{x:Type Button}">
    <Setter Property="FocusVisualStyle" Value="{StaticResource FocusVisual6}"/>
    <Setter Property="Background" Value="{StaticResource Button.Static.Background4}"/>
    <Setter Property="BorderBrush" Value="{StaticResource Button.Static.Border4}"/>
    <Setter Property="Foreground" Value="#FFFF"/>
    <Setter Property="BorderThickness" Value="1"/>
    <Setter Property="HorizontalContentAlignment" Value="Center"/>
    <Setter Property="VerticalContentAlignment" Value="Center"/>
    <Setter Property="Padding" Value="1"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type Button}">
                <Border x:Name="border" CornerRadius="5" Background="{TemplateBinding Background}" BorderBrush="Transparent" BorderThickness="{TemplateBinding BorderThickness}" SnapsToDevicePixels="true">
                    <ContentPresenter x:Name="contentPresenter" Focusable="False" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
                </Border>
                <ControlTemplate.Triggers>
                    <EventTrigger RoutedEvent="Button.Click">
                        <BeginStoryboard>
                            <Storyboard x:Name="Animation" RepeatBehavior="Forever" AutoReverse="True">
                                <DoubleAnimation Storyboard.TargetName="border"
                                                  Storyboard.TargetProperty="Width"
                                                  Duration="0:0:2" From="300" To="150"/>
                            </Storyboard>
                        </BeginStoryboard>
                    </EventTrigger>
                    <Trigger Property="IsDefaulted" Value="true">
                        <Setter Property="BorderBrush" TargetName="border" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}"/>
                    </Trigger>
                    <Trigger Property="IsMouseOver" Value="true">
                        <Setter Property="Background" TargetName="border" Value="{StaticResource Button.MouseOver.Background4}"/>
                        <Setter Property="BorderBrush" TargetName="border" Value="{StaticResource Button.MouseOver.Border4}"/>
                    </Trigger>
                    <Trigger Property="IsPressed" Value="true">
                        <Setter Property="Background" TargetName="border" Value="{StaticResource Button.Pressed.Background4}"/>
                        <Setter Property="BorderBrush" TargetName="border" Value="{StaticResource Button.Pressed.Border4}"/>
                    </Trigger>
                    <Trigger Property="IsEnabled" Value="false">
                        <Setter Property="Background" TargetName="border" Value="{StaticResource Button.Disabled.Background4}"/>
                        <Setter Property="BorderBrush" TargetName="border" Value="{StaticResource Button.Disabled.Border4}"/>
                        <Setter Property="TextElement.Foreground" TargetName="contentPresenter" Value="{StaticResource Button.Disabled.Foreground4}"/>
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>