Toyota on Wednesday announced a global recall of 7.43 million vehicles, including its popular Camry and Corolla models, over a possible fire risk, in a fresh blow to the firm's reputation for safety.

Japan's biggest automaker ordered the recall, which amounts to slightly more vehicles than it sold worldwide in its fiscal year to March, because of a fault with its electric windows.

"There is a defect in the driver's side power-window switch, which can cause earlier wear in the switch and lead to it malfunctioning," a Tokyo-based company spokeswoman told AFP.

"There is another concern that commercially-offered lubricant used to smooth the switch's movement can cause it to erode," she added.

The automaker said it first became aware of the glitch in 2008, but was unable to determine the cause until now.

About 2.47 million vehicles will be recalled from the United States, where at least one case of smoke coming from a window switch was recorded, the spokeswoman said.

"We cannot pinpoint its cause and there was no report of a fire."

A company spokesman told Dow Jones Newswires that the huge recall was not in response to any reported accidents but rather as a "protective measure".

A statement on the firm's US website said: "If commercially available lubricants are applied to the switch in an attempt to address the 'notchy' or sticky feel, melting of the switch assembly or smoke could occur and lead to a fire under some circumstances."

Another 2.8 million cars will be recalled from Europe and China while the remainder were from around the world including Japan, Canada, Australia and the Middle East, she said.

The affected vehicles with model years running from 2005 to 2010 include the Corolla, Camry, RAV4 sport utility vehicles, the Matrix hatchback, Vitz and Yaris subcompacts, the Scion xA and xD models, the Highlander and Sequoia SUVs and the Tundra pick-up truck.

Toyota, once lauded for its safety standards, has been forced into damage control in recent years after recalling millions of vehicles over defects.

Two months ago, it added two models to a controversial 2009 recall launched after floor mats became trapped under the accelerator and were linked to accidents that allegedly caused dozens of deaths.

Toyota's mishandling of the initial problem and other reports of sudden, unintended acceleration led to the recall of more than 12 million vehicles worldwide, a US congressional probe, more than $50 million in fines from US regulators and public apologies by its chief.

Toyota has since worked hard to regain its reputation for safety, while at the same time suffering from the impact of the economic crisis, a strong yen and the devastating 2011 quake and tsunami.

The firm did not supply the estimated costs of the recall announced Wednesday but last year it pegged costs incurred from some earlier call backs at about 180 billion yen ($2.3 billion).

The Japanese firm managed to regain its position as the world's number one automaker in the first half of 2012, stealing back the lead from US giant General Motors.

Wednesday's recall was the second blow for Toyota this week.

On Tuesday it said sales to China plunged nearly 50 percent last month as it suffered the impact of a territorial spat between Tokyo and Beijing that appears to be hitting trade between the economic giants.

Toyota's rivals Nissan and Honda also said Tuesday that their September sales in China -- the world's biggest vehicle market -- dropped by 35.3 percent and 40.5 percent respectively.

The two countries have for weeks been locked in a festering row over the islands in the East China Sea controlled by Japan but claimed by China.

Toyota's shares closed 1.9 percent lower at 2,943 yen in Tokyo on Wednesday.