The complicated deal that led Norfolk Southern to decide last year to move its headquarters to Midtown Atlanta was a triumph in city-state relations. The groundbreaking of the new complex this week came as that partnership faced new strains.

Gov. Brian Kemp and Atlanta Mayor Keisha Lance Bottoms were spotted laughing together before Tuesday’s ceremony. But behind the scenes, Bottoms has relentlessly lobbied him to oppose a Republican-backed measure to give the state control over Atlanta’s busy airport.

Bottoms has called that bill, which has passed the Senate and now awaits a House vote, tantamount to thievery of the city's most prized asset. And after the ceremony, Bottoms again urged lawmakers to abandon the attempt.

“This is the relationship we hope to continue to have with the state,” she said. “The conversation surrounding the airport is not helpful to this relationship. This is what success looks like. It was great to join the governor today. And I trust that we’ll be able to continue in the spirit of cooperation.”

Kemp has said only that he was carefully reviewing the measure. He hasn't endorsed it but, just as importantly, he also hasn't opposed it. It's an approach that contrasts with his predecessor, Gov. Nathan Deal, whose criticism of the measure effectively killed it before it reached a vote.

This year's effort, which narrowly cleared the Senate, is now caught up in a broader legislative tiff with Delta Air Lines. It was tied to what once was a tax-break bill and has since transformed into an effort to impose a big excise tax on fuel that airlines use.

City officials sound increasingly confident that House Speaker David Ralston, who is skeptical of the bill, will scuttle the effort. But the fact that it's gained any traction at all has worried city elders and business groups.

Caught in the middle was Jim Squires, the Norfolk Southern chief executive who pulled the trigger on the move. As one of the state’s leading business figures, he was asked his thoughts on the airport takeover bid.

He dodged the question, saying he had no opinion on the measure, but pointedly thanked Bottoms.

“Without her support, this project wouldn’t have happened,” he said. “We feel very fortunate to be coming to Atlanta under her leadership.”