Adjective
unforthcoming (comparative more unforthcoming, superlative most unforthcoming)
Not forthcoming; laconic or uncooperative
The coach's manner was dour and unforthcoming.
The leaders of the Wall Cult seem to be aware of the truth, but remain wholly unforthcoming.
And the two cabinet ministers in the Clark government he named as being unresponsive to, and unforthcoming about, serious allegations of transnational money laundering were, respectively, Coleman and de Jong. Source: Internet
It could also undermine them, which might be why officials are so unforthcoming on detail. Source: Internet