Tomašević was a member of the FR Yugoslavia national team (representing FR Yugoslavia) that won the gold medal at EuroBasket 1995 in Athens, Greece. Over three tournament games, he averaged 3.3 points and 3.0 rebounds per game. He was also a member of the FR Yugoslav Olympic team that won the silver medal at the 1996 Summer Olympics in Atlanta, Georgia, US. Over six tournament games, he averaged 6.2 points, 4.0 rebounds and 1.2 assists per game. Tomašević won the back-to-back gold medal at EuroBasket 1997 in Spain. Over eight tournament games, he averaged 4.5 points, 3.4 rebounds and 0.4 assists per game. He was also a member of the FR Yugoslavia team that won the gold medal at the 1998 FIBA World Championship in Greece. Over eight tournament games, he averaged 6.2 points, 5.7 rebounds and 0.9 assists per game.