The U.S. Capitol is seen along with a model of President Donald Trump's Triumphal Arch as visitors attend the fifth day of the Great American State Fair on the National Mall on June 29, 2026. Photo by Bonnie Cash/UPI | License Photo

July 9 (UPI) -- A federal Washington, D.C., planning agency advanced plans Thursday night for President Donald Trump's 250-foot triumphal arch, clearing a key procedural hurdle toward construction despite staunch opposition from historic preservation groups.

The National Capital Planning Commission approved preliminary site and building plans in an 8-1 vote, with three members voting present, during a meeting at its Washington headquarters.

The sole objector, Evan Cash, representing D.C. Council Chair Phil Mendelson on the panel, said he would not vote in its favor. He said the plans would "have the effect of upending decades of NCPC practice and thee century-old height framework."

According to the proposed plans, the arch would be constructed across the Potomac River in Virginia. At 250 feet tall and 166 feet wide, it would be twice the height of the Lincoln Memorial.