Several project nuget package. Unable to find package

I have to netstandard2.0 projects:

1. projectA/src/client/client.csproj
2. projectB/src/lib/lib.csproj

project A client reference project b lib like:

...<ItemGroup><ProjectReference Include="..\..\..\projectB\src\lib.csproj"><ReferenceOutputAssembly>true</ReferenceOutputAssembly><IncludeAssets>lib.dll</IncludeAssets></ProjectReference></ItemGroup><Target DependsOnTargets="ResolveReferences" Name="CopyProjectReferencesToPackage"><ItemGroup><BuildOutputInPackage Include="@(ReferenceCopyLocalPaths-&gt;WithMetadataValue('ReferenceSourceTarget', 'ProjectReference'))" /></ItemGroup></Target>...

I try to create nuget package: dotnet pack projectA/src/client.csproj --configuration Client

.nupkg contains lib.dll, but...

When I try to reference package to projectC I get projectC.csproj: [NU1101] Unable to find package projectB. No packages exist with this id in source(s): nuget.org

How to fix it?