Antonio Conte told Inter Milan fans on Saturday he needed time to turn Inter Milan into "a skyscraper" in European football.
Inter's season in Europe is over after finishing bottom of their Champions League group, a third consecutive financially-damaging exit in the first round.
"The fact that the league and Coppa Italia are all that remain for us is painful for me," Conte told a press conference before Sunday's Serie A game against Cagliari.
"Our elimination from the Champions League burns and those who know me know how I'm feeling about it.
"I want to send a message to Inter fans, we're not giving in to those who hope to destroy what we are trying to create after a year and a half of work.
"There is too much negativity, even if I understand that there is impatience after ten years without trophies.
"But we started from the ground up, we need time. Once the base has been built, one can think of the skyscraper, the kind Inter fans deserve."
Inter are second in Serie A, five points behind leaders AC Milan.
The 18-time champions have not won the league since 2010, having finished runners-up last season.
But Conte, who led Juventus to the first three in their current run of nine consecutive Serie A titles, said he had not shirked from the difficulties he knew existed when he took over in 2019.
"The situation wasn't the best but I knew that and I still wanted to try to take Inter back to where they deserve to be," continued Conte, who also won the Premier League and FA Cup with Chelsea.
"On a financial level, we knew that it'd be difficult due to the Covid emergency, but we remain united.
"Now we have to focus on the championship, then when the cups start again we will have, for now, two games fewer to play than the others.
"This is the advantage we have for now."
Conte, meanwhile, confirmed that Chilean midfielder Arturo Vidal remains out with a small muscular problem for the game against 11th-placed Cagliari.