Referee Steve Bennett booked both players after the incident

Defoe seemed to bite the arm of Javier Mascherano after he was fouled by the midfielder, with both players booked by referee Steve Bennett.

An FA spokesman said: "We are unable to take any action because the referee has already dealt with the incident.

"Fifa regulations prevent us from taking retrospective action."

Manchester City defender Ben Thatcher was punished by the FA after the event earlier this season when his forearm smash left Portsmouth midfielder Pedro Mendes in hospital.

However, that incident was deemed as exceptional because Mendes suffered serious injury but in most cases, the FA's hands are tied because of Fifa's stance on the issue of retrospective punishment.

Defoe felt his actions had been "blown out of all proportion".

"The referee was standing over me and if he felt I had done something bad he would have sent me off," said the 24-year-old.

"It doesn't look great on TV and I accept that I have a responsibility to conduct myself in the right way.

"When the West Ham player fouled me, I reacted in a bit of a mischievous way - my character is a little like that at times."

Sports minister Richard Caborn had earlier called for the FA to examine Defoe's actions.

In today's game, he could have been sent off

West Ham boss Alan Pardew

Caborn told The Times: "Any action like this I hope the authorities will decide on. Players in these positions have a responsibility to set a good example."

The incident came towards the end of the first half of Tottenham's 1-0 win at White Hart Lane.

Spurs boss Martin Jol described Defoe's bite as a "comical nibble".

"He was nibbling his arm - there will be no mark. Ask Mascherano if he has got a mark," said Jol.

"It is part of the game. They kicked him three times from behind in 10 minutes and he wanted to show his frustration in a nice, comical way."

However, Hammers boss Alan Pardew, who saw his side slide to a fifth straight Premiership defeat, did not see the funny side.

"Mascherano brought him down from behind and that was definitely a booking," he said.

"I didn't quite see the reaction from Jermain but it looked like he gestured towards Mascherano but whether there was any contact I don't know.

"In today's game he could have gone. If he was sent off there, it would have changed the game."