The Whites took the lead midway through the first half via Raphinha, but an own-goal from Junior Firpo and Michail Antonio's last minute strike ensured the Hammers left Elland Road with all three points.
Speaking after the game, Leeds boss Marcelo Bielsa said: “They are two teams with different realities I don't think that we deserved to lose. But I imagine that the opponents' manager thinks that they deserved to win.
“When a team finds themselves in a good moment, they obtain these rewards and when a team accumulates negative results you don't find a lot of things that they deserve.
He continued: “Our project of play was the same. When you conserve a result you stop doing some things that are necessary to avoid losing what you have obtained. There are responses which are sometimes natural, trying to hold on to what you have got.
“We spend too much time defending and not enough time in the opponents' half and defend too close to the goalkeeper, it is likely that the opponents chances to score increase.
“A succession of bad results, the absence of points, the position in the table they are all factors that affect the morale of any team. When the performance is not negative, the recovery is more probable.”
Next up, the Whites will look to bounce back next Saturday afternoon, when they host Watford in a must-win game at Elland Road.
Take a look at the latest news round-up from the Premier League, as the build-up to the weekend's action continues:
1. Reds urged to chase Sarr
Ex-footballer Kevin Phillips has tipped Liverpool to pursue a January move for Watford sensation Ismaila Sarr, whose stunning start to the season continued with his fourth goal in six games last weekend. He's been branded "an upgrade" on the Reds' existing backup attacking options. (Football Insider) Photo: Stephen Pond
2. Chelsea still want Chiesa
Chelsea's hopes of signing Juventus sensation Federico Chiesa in the next transfer window look to have taken a blow, with his club said to be determined to hold onto the Italian ace. He's been valued at around £86m. (Calciomercato) Photo: Gabriele Maltinti
3. Red Devils eye Mukiele
Man Utd have been tipped to make a move for RB Leipzig defender Nordi Mukiele, as they look to find quality cover for Aaron Wan-Bissaka. Mukiele is in the final two years of his current deal, and his side could cash in on their player in the next transfer window. (FourFourTwo) Photo: DANIEL ROLAND
4. Spurs could swoop for Kulusevski
Spurs have been linked with a move for Juventus forward Dejan Kulusevski. The £30m ace was named Serie A's best young player back in 2019/20, which saw him eventually seal his big-money move from Atalanta to his current side. (Mirror) Photo: MARCO BERTORELLO
5. Three sides race for Ramsey
Newcastle United, Everton and West Ham have all been credited with an interest in Juventus midfielder Aaron Ramsey, who could be allowed to leave the club on a free transfer. The ex-Arsenal star's hefty wages could prove a stumbling block for any potential suitors, however. (The Sun) Photo: Marco Rosi
6. Hammers could move for Bayo
West Ham have been linked with a move for Clermont striker Mohamed Bayo. The Guinea international, who is valued at £10m, scored 22 goals for his side last season, and played a key role in their promotion from Ligue 2 to Ligue 1. He's been tipped to provide competition for Michail Antonio up-front. (The Sun) Photo: JEFF PACHOUD