Unable to get rid of the Split package, several cans provide the same package

I have a main project (projectA) that has a library folder (projectB), and there is one in it package.subpackage. I would like to embed the library in the main project. The basic configuration of the project is quite simple (in addition to the description with the "compilation" area:

<plugin>
    <groupId>org.apache.felix</groupId>
    <artifactId>maven-bundle-plugin</artifactId>
    <version>2.4.0</version>
    <extensions>true</extensions>
    <configuration>
        <instructions combine.inherited="append">
            ...
            <Export-Package>package.*;version=${packet.version};-split-package:=merge-first</Export-Package>
            <Bundle-SymbolicName>${project.artifactId};singleton=true</Bundle-SymbolicName>
        </instructions>
    </configuration>
</plugin>       

But this gives the following warning

--- maven-bundle-plugin:2.4.0:bundle (default-bundle) @ projectA ---
Bundle project:projectA:bundle:version : Split package, multiple jars provide the same package:project/subproject
Use Import/Export Package directive -split-package:=(merge-first|merge-last|error|first) to get rid of this warning
Package found in   [Jar:., Jar:subproject]
Class path         [Jar:., Jar:subproject]

I have a split-package directive, but the warning persists.

What I would like to just insert all of the explicitly listed artifact and nothing more (even if there are more declared dependencies), without any transitive dependencies. Preferably without any warnings about the split package.