A long-planned, 600-foot-tall waterfront skyscraper in downtown Boston has been dealt another blow as Mayor Michelle Wu shifts her focus to another part of the city's waterfront.

The Wu administration said Wednesday it will launch a new municipal harbor plan for East Boston, while pushing back a similar zoning plan for 42 acres of downtown Boston's waterfront that has been debated for years, the Boston Globe reported.

Wu's administration intends to restart the process to create a new downtown plan, but first it is pushing forward on the plan for waterfront development in East Boston.

The downtown plan is needed for developer Don Chiofaro to move forward on his $1B, 600-foot-tall mixed-use tower on the site of the Boston Harbor garage, a project he has been in discussion for more than a decade.

The Chiofaro Co., which purchased the property for $153M in 2007, filed the third iteration of its plans in January 2020, calling for 538K SF of office, 258K SF of residential and 42K SF of public amenity space. The company told the Globe in a statement it remains committed to the investment and agrees with Wu's focus on climate resiliency and equity.

In addition to Chiofaro's project, the downtown plan would also pave the way for a 305-foot-tall tower planned on the Hook Lobster property, the Globe reported.

The state approved the downtown plan in 2018 after years of debate, but in April 2021 a Suffolk County judge threw out the zoning plan following a lawsuit from the Conservative Law Foundation and residents of a nearby condo complex, the Globe reported. In August, then-Mayor Kim Janey withdrew the plan, saying that it didn't go far enough to address climate resiliency and equity issues.

The Rev. Mariama White-Hammond, Boston's chief of environment, energy and open space, told the Globe that East Boston is "incredibly vulnerable" to sea level rise, and focusing on the area also displays the administration's emphasis on equity.

“We can’t say ‘equity’ and prioritize downtown over East Boston,” White-Hammond told the Globe. “Our commitment to equity requires us to focus on East Boston and not delay it anymore.”