Atlanta Mayor Keisha Lance Bottoms vetoed a measure the City Council approved last week giving the state control of a road bordering the Georgia Capitol in exchange for safety improvements to a busy Westside corridor.

In a letter obtained by The Atlanta Journal-Constitution that explains her decision, Bottoms argued that the city’s Charter prohibits individual Council members from negotiating with other governments on behalf of the city. She also said the Council did not give the proper public notice before voting to give up the short stretch of Mitchell Street, between the Coverdell Legislative Office Building and the State Capitol.

The legislation “violates both City ordinance and state law protecting the separation of powers,” Bottoms said in a prepared statement to the AJC.

A mayor’s office representative said while opposing the measure during the council meeting last week that $6 million has already been set aside for improvements to Donald Lee Hollowell Parkway.

Georgia lawmakers have wanted to close the block of Mitchell Street to car traffic for years, citing safety and security concerns.

With the mayor’s veto, the measure will head back to the full Council. The 15-member legislative body can override a mayoral veto with a two-thirds majority vote.

The City Council ordinance passed by a vote of 12-1 last week. It said that in return for getting the street, the state has agreed to “cooperate with the city” on safety improvements to Hollowell Parkway, a state route on the Westside that has seen a high number of pedestrian deaths in recent years.

A Georgia Department of Transportation spokeswoman, however, told the AJC last week that a project to improve safety on Hollowell is already underway and in the scheduling phase — the result of a collaboration between GDOT and the Atlanta Department of Transportation.

Bottoms’ letter, which was sent to the Council on Tuesday, referenced GDOT’s statement to the AJC and said her office agrees the city should support GDOT’s project to make Hollowell a safer road.

During last week’s meeting, Rashad Taylor, a senior advisor to Bottoms, told the Council that the mayor’s office was unaware of any formal negotiations between the city and state on the issue.

Councilman Michael Julian Bond, who co-sponsored the legislation, told the AJC last week that the Council got involved “out of necessity and frustration.” He added that Hollowell has been dangerous for years.

After reading the veto letter Wednesday, Bond said he disagreed that there had been any violation.

He said he understands Bottoms has worked to raise the $6 million through private partners. But Bond said the city getting involved would only slow down the process.

Bond said Westside residents “are suffering over these endless arguments about technicalities and ego.”

Currently, the city has blocked off the short stretch of Mitchell Street between the Capitol and Coverdell building to cars and trucks during the legislative session due in part to security concerns.

Bottoms’ letter about the veto argues that state law would require the city to hold public hearings and notify MARTA and Grady Memorial Hospital, which is located about half a mile from the Capitol, before giving the state control of Mitchell Street.