A furious Tuchel was in no mood to celebrate after Jude Bellingham's two goals secured another nervy come-from-behind victory for the Three Lions at Miami's Hard Rock Stadium.
“We made life very, very difficult for ourselves today," Tuchel said in an on-field interview moments after his team's win.
"The result is fantastic. The last four is amazing, but I'm not happy with the performance.
"The commitment is there, but it made life very, very difficult for us in the way we played, how we played, sloppy, lots of safety, not fast enough, not enough. We were lucky today."
England will now face either Argentina or Switzerland in Atlanta on Wednesday as they attempt to reach their first World Cup final in 60 years.
Tuchel though was adamant that his team would need to make an improvement to progress further in the competition.
"We need to get better," Tuchel said. "Now it's celebration, and now it's taking it all in. We have three days."
World Cup 2026
The 2026 World Cup will be held from June 11th to July 19th in the United States, Canada and Mexico. The tournament will feature 48 national teams and will be played in 16 modern stadiums.
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