Sankhwalkar was first picked in the national side in 1975, following his success at the club level. He played for the team at the AFC Youth Championship in Kuwait in that year and also the following year. He was a part of the team that participated at the Marah Alim Cup in Kabul in 1976 and 1977, the Merdeka Cup in 1976, 1981, 1982 and 1986.
Sankhwalkar's inclusion on the national team was a result of his achievements at the club level. He represented the country in several international competitions, notably the AFC Youth Championship, Marah Alim Cup, Merdeka Cup, and others.