DETROIT — Shares of Ford Motor Co. (F) jumped more than 4% Wednesday as investors responded to a report the struggling auto maker is interested in potentially joining the alliance between Renault SA (13190.FR) and Nissan Motor Co (NSANY).

Ford Chief Executive Bill Ford recently approached Renault/Nissan Chief Executive Carlos Ghosn about the possibility of a partnership, according to The Wall Street Journal Wednesday.

Renault/Nissan currently is in talks with General Motors Corp. (GM) about a potential alliance and a decision on a deal between the two parties is due in October.

GM and Renault/Nissan have given little information on the progress of the talks. GM Chief Executive Rick Wagoner recently said the company remains focused on its own restructuring efforts and is leaving the exploratory talks with Renault/Nissan to a small team.

Ford spokesman Oscar Suris said Ford is not commenting on speculation surrounding Bill Ford’s plans regarding alliances.

“Right now we are focused on the 90-day study with GM and we will wait until the outcome of that study is complete,” Renault/Nissan spokesman Simon Sproule said in an email. “Anything more is speculative at this stage.”

In recent weeks, Bill Ford has expressed interest in a potential alliance with another auto maker and the company currently is conducting an internal review of its assets in order to devise future strategies.

Recently, Ford shares were up 4%, or 30 cents, at $7.72 on volume of 13.3 million. Ford’s 7.45% notes due 2031 are down a point at 75.5 cents on the dollar. Ford Motor Credit’s 9.875% notes due 2011 are up more than 1/2 point at 101 7/8, according to MarketAxess, an electronic trading platform for corporate bonds.

The auto maker’s shares have gained about 25% over the past month since the auto maker announced it is accelerating its North American restructuring efforts. Ford announced its “Way Forward” restructuring in January, but escalating headwinds, such as high gasoline prices, and a deeper-than-expected slump in pickup truck sales is leading the auto maker to speed its efforts.

Ford will announce its comprehensive restructuring update in mid-September. Last week, the auto maker gave a glimpse of its agenda, saying it will cut fourth-quarter North American vehicle production by 21%, with most of the output decline coming from truck production cuts.

Production cuts are only a portion of what is expected from Ford’s updated revival plan. The auto maker is currently considering cutting salary-related costs and headcount by between 10% and 30%.

Various news reports suggest Ford is also mulling expanding its blue-collar attrition efforts by offering a broad-based early retirement and buyout package to its entire American hourly workforce. Such a deal would be patterned after GM’s accelerated attrition effort, staged earlier this year. GM managed to cut 34,400 jobs via the initiative, speeding its job-cut target up by two years.

In January Ford stated its plan to cut 30,000 hourly jobs in North America and close 14 plants by 2012. It plans to shave about 12,000 of those jobs in 2006, and it may add additional plants to its list of closures under the revised Way Forward.