"I would say that it is the final World Cup with the current refereeing system," Jerome Valcke, general secretary of world football's governing body, told the BBC.
FIFA's past resistance to change appears to be shifting after some wrong calls in the World Cup, most notably Frank Lampard's disallowed effort for England against Germany that crossed the goalline, and Carlos Tevez's offside goal for Argentina versus Mexico.
Tevez's goal was replayed on stadium big screens, heightening fury among Mexican players and fans.
Valcke said the failure to award Lampard's effort was a "bad day" for organisers.
"We are talking about a single goal not seen by the referee which is why we are talking about new technology," he said in an interview with the British broadcaster.
"But again let's see if this system will help or whether giving the referee an additional four eyes will give him the comfort and make duty easier to perform, then why not?"
The use of two extra linesmen to check the goalline and penalty area was trialled in the Europa League last season and is to be used in the upcoming Champions League, from the final qualifying round, and Euro 2012 qualifiers.
FIFA president Sepp Blatter has apologised for the mistakes in South Africa and said it would be a "nonsense" not to look again at the merits of goalline technology such as the Hawk-Eye system used in tennis and cricket.
Valcke said the increased speed of modern soccer had hastened the need for reform.
"The game is different and the referees are older than all the players," he said.
"The game is so fast, the ball is flying so quickly, we have to help them and we have to do something and that's why I say it is the last World Cup under the current system."
The FIFA official said football's lawmaking body, the International Football Association Board (IFAB), was unlikely to hold serious discussions on the matter at their next meeting later this month, but rather when they sit again in October.
