"The only Boeing job that should leave this country is his," said Jon Holden, president of International Association of Machinists District 751, which represents more than 30,000 workers at Boeing.

"This is one more example of how Jim McNerney operated during his years as Boeing's CEO - threatening the livelihood of his employees and jeopardizing the communities they live in order to get what he wants. Enough is enough. It is time for him to go," Holden said.

McNerney, who stepped down as chief executive on July 1, said earlier on Wednesday that Boeing was actively considering moving "key pieces" of its operations to other countries because Congress has not re-authorized the Ex-Im Bank's charter, which expired on June 30.

Holden said the machinists union, like McNerney, supports the Ex-Im bank, which it says provides important financing to allow airlines to buy Boeing jetliners built by union members.

"Any politician who is fighting reauthorization of the bank is working to destroy" an institution that helps the U.S. economy, workers and taxpayers, he said. "We share his frustration with Congress."

But for McNerney "to continue to threaten to take our jobs away is unacceptable," he added.

The comments follow a bitter fight between Boeing and its machinists in 2013, when Boeing threatened to move production of its next new jetliner, the 777X, out of Washington state unless union members voted for a contract extension that would sunset their defined-benefit pension program.

The contract was narrowly approved in early 2014, and later that year McNerney joked on a conference call that employees were "still cowering." Though he quickly apologized for the comment, it inflamed union members.

Members of Boeing's other major union, the Society of Professional Engineering Employees in Aerospace, said they also support Ex-Im reauthorization, but declined to comment on McNerney's remarks.

(Reporting by Alwyn Scott; Editing by Jonathan Oatis)