diff --git a/src/SharedKernel/Helpers/PhoneUtil.cs b/src/SharedKernel/Helpers/PhoneUtil.cs
index 4961809..1884bbb 100644
--- a/src/SharedKernel/Helpers/PhoneUtil.cs
+++ b/src/SharedKernel/Helpers/PhoneUtil.cs
@@ -14,7 +14,6 @@ public static bool TryFormatArmenianMsisdn(string? input, out string? formatted)
 
       var s = input.Trim();
 
-      // Special-case exact "(374)" prefix
       if (s.StartsWith("(374)", StringComparison.Ordinal))
       {
          var rest = DigitsOnly(s.AsSpan(5));
@@ -28,7 +27,6 @@ public static bool TryFormatArmenianMsisdn(string? input, out string? formatted)
          return false;
       }
 
-      // General tolerant parse: allow spaces, dashes, dots, parentheses; '+' only at start
       var sb = new StringBuilder(s.Length);
       for (var i = 0; i < s.Length; i++)
       {
@@ -58,6 +56,8 @@ public static bool TryFormatArmenianMsisdn(string? input, out string? formatted)
       ReadOnlySpan<char> last8;
 
       var plusAtStart = s[0] == '+';
+      var doubleZeroAtStart = s.StartsWith("00", StringComparison.Ordinal);
+
       if (plusAtStart)
       {
          if (span.Length == 11 && span.StartsWith("374".AsSpan()))
@@ -72,20 +72,36 @@ public static bool TryFormatArmenianMsisdn(string? input, out string? formatted)
       }
       else
       {
-         switch (span.Length)
+         // Handle "00" international prefix for Armenia: "00374" + 8 digits => total 13 digits
+         if (doubleZeroAtStart && span.Length == 13 && span.StartsWith("00374".AsSpan()))
+         {
+            last8 = span[5..]; // skip "00" + "374"
+         }
+         else
          {
-            case 11 when span.StartsWith("374".AsSpan()):
-               last8 = span[3..];
-               break;
-            case 9 when span[0] == '0':
-               last8 = span[1..];
-               break;
-            case 8:
-               last8 = span;
-               break;
-            default:
-               formatted = input;
-               return false;
+            switch (span.Length)
+            {
+               case 11 when span.StartsWith("374".AsSpan()):
+               {
+                  last8 = span[3..];
+                  break;
+               }
+               case 9 when span[0] == '0':
+               {
+                  last8 = span[1..];
+                  break;
+               }
+               case 8:
+               {
+                  last8 = span;
+                  break;
+               }
+               default:
+               {
+                  formatted = input;
+                  return false;
+               }
+            }
          }
       }
 
diff --git a/src/SharedKernel/SharedKernel.csproj b/src/SharedKernel/SharedKernel.csproj
index 41f0bca..362350d 100644
--- a/src/SharedKernel/SharedKernel.csproj
+++ b/src/SharedKernel/SharedKernel.csproj
@@ -8,7 +8,7 @@
         <PackageReadmeFile>Readme.md</PackageReadmeFile>
         <Authors>Pandatech</Authors>
         <Copyright>MIT</Copyright>
-        <Version>1.6.5</Version>
+        <Version>1.6.6</Version>
         <PackageId>Pandatech.SharedKernel</PackageId>
         <Title>Pandatech Shared Kernel Library</Title>
         <PackageTags>Pandatech, shared kernel, library, OpenAPI, Swagger, utilities, scalar</PackageTags>
diff --git a/test/SharedKernel.Tests/PhoneUtilTests.cs b/test/SharedKernel.Tests/PhoneUtilTests.cs
index 0faca2f..fde30cc 100644
--- a/test/SharedKernel.Tests/PhoneUtilTests.cs
+++ b/test/SharedKernel.Tests/PhoneUtilTests.cs
@@ -5,12 +5,14 @@ namespace SharedKernel.Tests;
 public class PhoneUtilTests
 {
    [Theory]
+   [InlineData("0037493910593", "+37493910593")]
    [InlineData("+37493910593", "+37493910593")]
    [InlineData("37493910593", "+37493910593")]
    [InlineData("093910593", "+37493910593")]
    [InlineData("93910593", "+37493910593")]
    [InlineData("(374)93910593", "+37493910593")]
    // tolerant separators
+   [InlineData("00 374 93 910-593", "+37493910593")]
    [InlineData("+374 93 910 593", "+37493910593")]
    [InlineData("374-93-910-593", "+37493910593")]
    [InlineData("(374) 93 910 593", "+37493910593")]
@@ -24,6 +26,10 @@ public void Formats_Armenian_Numbers_When_Valid(string input, string expected)
    [Theory]
    [InlineData("+12025550199")] // foreign
    [InlineData("441234567890")] // foreign
+   [InlineData("+7123-4567-901")] // Russian 1
+   [InlineData("+71234567901")] // Russian 2
+   [InlineData("+7 123 4567 901")] // Russian 2
+   [InlineData("+7-123-4567-901")] // Russian 3
    [InlineData("+++37493910593")] // invalid
    [InlineData("37493A10593")] // invalid char
    [InlineData("(374)1234567")] // only 7 digits after prefix