Datamapper Codeigniter use condition in where_related clause

Question

Table Structure

I have three Database tables as :
1.)  Deal_Team
     id, deal_id, title, status, insert_time
2.) Deal_Team_User
     id, deal_team_id, user_id, status, insert_time
3.) Attachment_To_Deal_Team
    id, attachment_id, deal_team_id, insert_time

PHP Code is as follows:

$objDealTeam = new Deal_Team();
$objDealTeam->where_related('deal_team_user', 'user_id', $user_id);
$objDealTeam->where_related('attachment_to_deal_team' , 'id >=' ,'0' );
echo $objDealTeam->get_sql(NULL,NULL,TRUE);die;

Built Query for above code :

SELECT depl_deal_team.* FROM (depl_deal_team) LEFT OUTER JOIN depl_deal_team_user depl_deal_team_user ON depl_deal_team.id = depl_deal_team_user.deal_team_id LEFT OUTER JOIN depl_attachment_to_deal_teams depl_attachment_to_deal_teams ON depl_deal_team.id = depl_attachment_to_deal_teams.deal_team_id WHERE

depl_deal_team_user.user_id = '10' AND depl_attachment_to_deal_teams.id = '0'

Desired Query:

SELECT depl_deal_team.* FROM (depl_deal_team) LEFT OUTER JOIN depl_deal_team_user depl_deal_team_user ON depl_deal_team.id = depl_deal_team_user.deal_team_id LEFT OUTER JOIN depl_attachment_to_deal_teams depl_attachment_to_deal_teams ON depl_deal_team.id = depl_attachment_to_deal_teams.deal_team_id WHERE

depl_deal_team_user.user_id = '10' AND depl_attachment_to_deal_teams.id >= '0'

Thanks In Advance