Ex-Moreno Valley City Councilman Marcelo Co, 64, will plead guilty to one count each of bribery and filing a false tax return, according to court records. He could face up to 13 years in prison and will make his first court appearance next month.
A message left for Co's attorney, Brian Newman, was not immediately returned.
Authorities said Co promised an undercover FBI operative who posed as a real estate broker that he could control a voting majority of the council to sway land use decisions.
Records show that Co eventually agreed to sell a 30-acre parcel he owned to the operative for $5.3 million. The land was only appraised at $710,000, but Co said once zoning laws were changed by the council the parcel would increase in value 500 percent, court documents say.
"Mr. Co orchestrated an elaborate and brazen scheme to undermine the democratic process in Moreno Valley," said U.S. Attorney Andr Birotte Jr. "Whether he was motivated by power or greed, these crimes constitute a wholesale violation of his oath to work for the citizens who elected him."
Thom Mrozek, a spokesman for the U.S. attorney's office, said the bribe is believed to be the largest taken by a public official in an undercover operation.
At a meeting in January, Co and the operative met and agreed that publicly filed documents would reflect a $3 million sales price for Co's land. Authorities said Co then took $2.3 million in cash.
A grainy surveillance photo released by federal investigators shows a large stack of money on a table in front of Co.
Co was elected to the council in November 2010 and resigned from his seat in August after being charged in state court in an unrelated welfare fraud case.
Moreno Valley is about 60 miles east of Los Angeles.