Thomson Reuters
The guidance, which The Journal said would be issued in the coming days, would stop funding for procedural medical treatments for transgender service members.
The directive would give Secretary of Defense James Mattis six months to prepare for the proposed plan, according to The Journal. Mattis is also expected to weigh a transgender person's ability to deploy as the primary legal basis to determine whether to remove them from the military.
Trump initially floated the new policy in a series of tweets in July, claiming that the military "cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail."
Trump's statement sparked backlash from LGBTQ-rights groups and caused confusion amongst military service members, as the Pentagon and the White House attempted to defer media inquiries on the matter to each other.
After Trump's apparent reversal of President Barack Obama's directive to end the ban on transgender service members, Reuters reported earlier this month that five transgender service members, including veterans of recent wars, sued Trump, claiming that his tweets violated their rights to due-process and equal protection under the law.