Regular Expression (Regex) for Phone number with Country code and 10 digits

Please refer this HTML code

<asp:TextBox ID="txtPhone" runat="server" />
<asp:RegularExpressionValidator ErrorMessage="Invalid" ControlToValidate="txtPhone"
    ValidationExpression="^[+]{1}[0-9]{12}$" runat="server" />
<asp:Button Text="Save" runat="server" />

Thaks a lot for responces

I got it exact what I want

"^\+(?:[0-9]●?){6,14}[0-9]$"