Complex sentence: In June 2016, the New York Times published an editorial opposing India's entry into the Nuclear Supplier's Group (NSG) while the US administration led by President Barack Obama was supporting India's membership.
Split into simpler sentences: In June 2016, the New York Times published an editorial opposing India's entry into the Nuclear Supplier's Group (NSG). During this time the US administration led by President Barack Obama was actively supporting India's membership.