General Motors chief finance officer Chris Liddell is leaving the automaker, reportedly because he was passed over for the top job there, but has no specific future plans, apart from not being a CFO again.

“Liddell today announced that he will leave the company 1 April, 2011, having completed the largest public offering in history and stabilising the company’s financial operations,” GM said in a statement.

New Zealand-born Liddell, 52, joined GM in January 2010 to head the company’s global financial and accounting operations.

Reuters noted that Liddell left Microsoft, where he was CFO, in November 2009 to look for a bigger job. When he joined GM, he was seen as a well-regarded outsider who could possibly succeed then-CEO Ed Whitacre when he stepped aside.

Microsoft said when Liddell left that he was looking at opportunities to “expand his career beyond being a CFO”, according to Reuters.

However, GM named Dan Akerson, 62, as CEO last August, immediately leading to industry speculation that Liddell would eventually leave.

“The decision to leave was Chris’s,” GM spokeswoman Lori Arpin told Reuters. “He came here to be CFO and with the company on proper footing, he decided that it was the right time personally and professionally to pursue other opportunities. He has not announced his future plans yet.”

“Chris was a major contributor during a pivotal time in the company’s history,” said Akerson, also GM’s chairman, in a statement.  “He guided the company’s IPO process and established a good financial foundation for the future.”

“I’ve done most of what I hoped to achieve as CFO and it’s time to move on,” the Wall Street Journal quoted Liddell as saying. “I won’t be a CFO again. I’ve been CFO at a few companies now and I feel like I’ve achieved all I can achieve in that role.”

Liddell added that he has “thoughts and ideas” about what he’ll do next but “no specific plans” at this time. “I prefer a clean break,” he said.

Dan Ammann will succeed Liddell – he is currently GM vice president, finance and treasurer.

“Dan’s depth of knowledge of the financial community and our business will be instrumental as we continue to earn the trust of global investors and customers,” said Akerson.  “He is held in high regard on Wall Street and within the company and, as we move our financial strategy forward, his credibility and leadership will be invaluable.”

Since joining the company in March, 2010, Ammann headed the automaker’s treasurer’s office, based in New York, with operations around the world.  Prior to GM, Ammann was managing director and head of Industrials Investment Banking for Morgan Stanley.

“I came to General Motors to be part of something great,” said Liddell.  “My objective was to help rebuild this iconic company and I am particularly pleased that through this process, we have also developed a strong successor in Dan Ammann.”

A successor for Ammann will be announced later.