TOKYO — Toyota acknowledged that is has begun fixing problems with the brakes in its prized Prius, but remains undecided about a recall, adding to the catalog of safety woes — and muddled responses — at the Japanese automaker.

Toyota Motor Corp., already reeling from massive global recalls involving faulty gas pedals in other cars and trucks, said today that Prius models sold since late last month, including those shipped overseas, had the problem with the antilock brake system corrected.

But that still leaves the potential flaw in Priuses sold in Japan and overseas before late January. And while Japan's transport minister urged Toyota to consider a recall of the Prius and said he is ordering an investigation into the brake problem, Toyota executive Hiroyuki Yokoyama said the company hasn't yet decided if a recall is necessary.

The U.S. Transportation Department said today it has opened an investigation into brake problems in the 2010 model year Prius.

The National Highway Traffic Safety Administration told The Associated Press it has received 124 reports from consumers, including four reports of crashes. The investigation will look into allegations of momentary loss of braking capability while traveling over uneven road surfaces, potholes or bumps.