(CNN) -- Fernando Alonso refused to comment on Renault's upcoming hearing about alleged race-fixing at last year's Singapore Grand Prix as he chose to focus on this weekend's race in Monza.
Fernando Alonso won the 2008 Singapore Grand Prix after Renault teammate Nelson Piquet Jr. crashed.
The Spaniard's Renault team face a probe from world motorsport's governing body the FIA on September 21 over claims that Nelson Piquet Jnr crashed on purpose, making it easier for his teammate to win the race due to the introduction of the safety car.
Piquet, who was sacked by Renault after the Hungarian Grand Prix in late July after failing to score a point this year, has reportedly already made a sworn statement about his involvement.
However, two-time Formula One world champion Alonso gave little away at a press conference on Thursday ahead of the Italian Grand Prix.
"For me, it's difficult to understand this situation and these investigations," the 28-year-old said. "It's another day. I'm preparing for this grand prix, trying for a good result here. I'm fully concentrated on the job.
"Of course, I'm very surprised. I can't imagine this situation, but it's time to start thinking about this race. I'm not spending any time on this.
"After the hearing on the 21st everything will be clarified, and that will be the time to say something."
Piquet was outspoken in his criticism of influential billionaire Renault boss Flavio Briatore after his departure, but Alonso believes the Brazilian still has a future in F1.
"We were teammates for a year and a half, and I never had a problem with him. He has the talent to be in Formula One," Alonso said.
"After a year and a half with Renault in not the most competitive car, he needs a competitive car. I'm sure he is capable of good results in the future."
The F1 future of Briatore, and his Renault team, would be in major doubt if they are found guilty by the FIA, but Alonso backed his boss.
"He is nice person, a nice boss with me," he said. "He is a friend who has always supported my career from the time I was at Minardi.
"Flavio is one of the good people here, and he always has my support."
Meanwhile, Ferrari -- who have been linked with a move for Alonso in 2010 -- announced on Thursday that Banco Santander will be one of the team's title sponsors for the next five years.
The Spanish banking group had sponsored Ferrari's rivals McLaren for the past three seasons, but decided not to renew the deal.