Varane, who headed home Antoine Griezmann's free kick to open the scoring for France in their 2-0 quarter-final victory over Uruguay on Friday, said he was pleased at how France's relatively young team was maturing as they progressed.
"I'm happy to have been decisive (by scoring). It's a great pleasure," the Real Madrid centre back told reporters on Saturday. "We were faced with a physical challenge yesterday and we dealt with it.
"Experience counts in these big competitions and it helps to avoid small mistakes. We have a relatively young team, but we've shown maturity and have been growing since the tournament started.
"We're solid defensively and have been able to adapt to our opponents. We can also vary our game, which it is a massive strength."
Belgium showed plenty of attacking flair in their 2-1 win over Brazil in the other quarter-final and Varane singled out forward Romelu Lukaku and playmaker Eden Hazard as two of the players the French would have to be wary off.
"It's a World Cup semi-final... there are no favourites," he added. "We'll have to outdo ourselves and give our best, take each match as it comes, and see how far we can go.
"Belgium are young, but they are maturing. We know it will be a tough match.... Romelu Lukaku's physicality can trouble any defence. We can't leave him any space because he's a quality player.
"As for Eden, I've already played against him when he was at Lille. He has great qualities and is a good dribbler. We can't give him any space either, so it is going to take a collective effort."
(Reporting by Simon Jennings , editing by Clare Lovell)
