The club have also been reprimanded but they will be allowed to continue to play in this year’s competition.
Sakho, 25, had been due to join up with his national side at the Africa Cup of Nations but the Hammers informed the Senegalese FA that injury would prevent him from travelling to the tournament.
On January 25, Sakho came off the substitutes’ bench to score the only goal of the tie at Ashton Gate – prompting protest from the Senegalese authorities.
West Ham issued a brief statement following FIFA’s decision.
“The club and the player have received the decision and will now be focusing their concentration on the game against Manchester United on Sunday,” it read.
A FIFA statement read: “FIFA can today confirm the decisions of its Disciplinary Committee in the case involving the English club West Ham United and the player Diafra Sakho.
“Diafra Sakho was called up by the Senegalese Football Association on 18 December 2014 to play for Senegal in the Africa Cup of Nations 2015 taking place in Equatorial Guinea between 17 January and 8 February 2015, as well as to attend the training camp of the said representative team from 5-16 January 2015 in Morocco.
“The Senegalese FA was informed by West Ham United that Sakho was prevented from playing and travelling by plane due to injury and thus he did not join the Senegal team.
“On 25 January 2015, the player took part in an official match for his club West Ham United. Senegal were eliminated from the Africa Cup of Nations 2015 on 27 January 2015.
“In view of the above and in accordance with art. 6 par. 1 of Annexe 1 of the FIFA Regulations on the Status and Transfer of Players (hereinafter the Regulations), disciplinary proceedings were opened against the player and the club for a potential violation of Annexe 1 of the Regulations.
“The FIFA Disciplinary Committee has found the club and the player to have violated art. 5 of Annexe 1 of the Regulations in relation to the match played by Sakho on 25 January 2015. The club has been fined CHF 100,000 in accordance with art. 10 c) and art. 15 of the FIFA Disciplinary Code (FDC) and issued with a reprimand, while the player has been sanctioned with a reprimand in accordance with art. 10 b) and art. 14 of the FDC.
“The terms of the decisions were notified to the relevant parties today.”
Both Sakho and West Ham have been cleared to play in the next round as scheduled, where Sam Allardyce’s side face West Brom.
But Bristol City issued a a brief statement of their own following FIFA’s ruling, hinting that this may not be the end of the matter as far as they are concerned.
“Bristol City FC notes FIFA’s decision with regards to the Disciplinary Committee’s case against West Ham United and their player Diafra Sakho,” the statement read.
“The club is disappointed with the penalty handed down by the FIFA Disciplinary Committee and is considering its options.
“The club will be making no further comment at this time.”