Toyota Motor on Wednesday announced it would recall 3.37 million vehicles worldwide over air-bag and emissions defects.

The automaker said that welds that connect side-curtain air bags could deteriorate over time, causing the devices to inflate without cause. The recall covers Toyota Prius models from 2009 through 2015 and Lexus CT200 models from 2010 through 2015. The total accounts for 1.4 million vehicles, 482,000 of them in the United States, Toyota said in the announcement.

Additionally, 2.87 million vehicles internationally are being recalled for possible cracks in the fuel tank, Toyota said. Some Prius models are affected by both defects the company said, as are the Auris, Corolla, Zelas, Lucas and Lexus HS250h and CT200h manufactured from 2006 through 2015. Roughly 900,000 Priuses are affected by both defects, which brings the total vehicles recalled to 3.37 million. Most vehicles with fuel-tank issues were sold in Japan and China.

As of this week, Toyota officials said, the company was unaware of any injuries or fatalities related to either recall.

Owners who are affected by the air-bag recall can bring their vehicles to a Toyota or Lexus dealership to have retention brackets installed on the air bags free of charge, the company said.

The latest air-bag issues are unrelated to another recall of 60 million vehicles worldwide from multiple automakers that have Takata air bags, Toyota said.

That recall is the largest auto recall ever. Vehicles with Takata's devices were recalled after investigators in 2014 found that the air bags were liable to shoot shrapnel toward drivers while inflating. Those air bags have been linked to 14 deaths and more than 100 injuries worldwide.

Air bags in Wednesday's recall were not made by Takata but by Sweden-based Autoliv, which said in a statement that it is cooperating with Toyota and American and Japanese authorities.

In seven cases, according to Autoliv, air bags partially inflated without a deployment signal in unoccupied parked cars.

"Safety and quality are our priorities and we are fully committed to support Toyota's action in resolving this issue, and will support Toyota in the implementation of solution to the issue," Jan Carlson, Autoliv president and chief executive, said in a statement.

Autoliv's stock closed down 1.4 percent on the news. Toyota ended the trading day up 1.7 percent.

Wednesday's recall follows another major one by Toyota in February, when 1.1 million RAV-4 models were recalled over a seat-belt problem. During a frontal collision, the metal seat cushion frame could sever the car's back row seat belts and not restrain passengers. Earlier that month, Toyota had recalled 320,000 vehicles, Land Cruisers, 4Runner, Tundras and Sequoias, and Lexus LX470s and GX470s, over a programming defect that caused side-curtain air bags to deploy upon starting the vehicle.

In 2009 and 2010, the company recalled 9 million vehicles over "sticky" accelerators, gas pedals that did not release.

Taken together, Wednesday's recalls are the third largest in Toyota history.