Entity framework data annotation of foreign key without a navigation property

I have the following table definition:

public partial class ClientClassification
{
    [Key, Column(Order = 0)]
    public long ClientId { get; set; }

    [Key, Column(Order = 1)]
    public ClientClassificationEnum ClientClassificationType { get; set; }

    [ForeignKey("ClientId")]
    public virtual Client Client { get; set; }
}

ClientId is a foreign key into the Client table. This is a many to 1 relationship (a client can have many classifications). Is there any way I can omit the Client navigation property but still declare this foreign key relationship? So something like:

public partial class ClientClassification
{
    [Key, Column(Order = 0)]
    [ForeignKey("Client.ClientId")]
    public long ClientId { get; set; }

    [Key, Column(Order = 1)]
    public ClientClassificationEnum ClientClassificationType { get; set; }
}