Manchester United's 4-1 win over Chelsea on Thursday ended Liverpool's slim hopes of making the top four.
Liverpool finished second in the Premier League last season and won both domestic cup competitions before losing to Real Madrid in the Champions League final.
Jurgen Klopp's side have largely underwhelmed in the current campaign bar a ten-game unbeaten run at the tail end of the season.
Salah feels Liverpool only have themselves to blame for missing out on Europe's elite club competition next term as they will have to content with a Europa League spot with their fifth place finish.
“I’m totally devastated. There’s absolutely no excuse for this,” the Egypt international, who rarely makes public statements, wrote in a strongly-worded post on Twitter.
“We had everything we needed to make it to next year’s Champions League and we failed.
“We are Liverpool and qualifying to the competition is the bare minimum.
“I am sorry but it’s too soon for an uplifting or optimistic post.
“We let you and ourselves down.”
Salah has scored 30 goals and assisted 15 times in 50 appearances across all competitions this season.
