The men accused of corrupting Gov. Cuomo’s “Buffalo Billion” economic development program by rigging bids were congratulating themselves on their “partnership” months before the process for choosing developers even kicked off, it emerged in court Tuesday.

“I am looking forward to our partnership to help advance Gov. Cuomo’s innovation-driven economic prospects,” Cuomo’s “economic guru” Alain Kaloyeros wrote in an email to an executive of construction company Cor Development in July 2013 — well before the search for developers to build in Buffalo and Syracuse using state money was made official, the evidence showed.

“I am truly grateful for the opportunity to meet with you and work with you in the future,” Cor Development executive Steven Aiello responded.

The email exchange was facilitated by corrupt lobbyist Todd Howe, who has pleaded guilty to accepting bribes from developers seeking state development work, evidence showed.

Prosecutors have said that the emails will clinch their case against four men they say rigged bids for hundreds of millions of dollars in government construction contracts.

Also on trial is Joseph Gerardi of Cor Development and Louis Ciminelli of LP Ciminelli.

Separately Tuesday, the defense focused on undermining the government’s theory that Kaloyeros rigged bids in order to keep Cuomo on his good side by showing that the two were already close by 2013, when the alleged bid rigging started.

In cross examining a high-ranking member of the de Blasio administration, they asked about Kaloyeros’ relationship with Cuomo.

First Deputy Mayor Dean Fuleihan, who was working with Kaloyeros at SUNY in 2013, said he got the impression from Kaloyeros that he and the governor were on great terms.

“My sense from conversations was that Dr. Kaloyeros felt secure in that relationship,” Fuleihan told the jury. “My perception was that it was positive … based on announcements that the college was making that the governor was participating in,” Fuleihan said.

Earlier, the defense also tried to enter into evidence a 2013 Buffalo News article that showed Cuomo heaping praise on Kaloyeros in 2013 by calling him a “visionary” and a “real gift to the state.”

The judge said no, calling it hearsay.