Palestinian authorities said a grave site discovered at the Nasser hospital, the main medical facility in central Gaza, contained nearly 400 bodies
In the comments reported by TASS and RIA, Ryabkov did not specify what those steps would be.
He said the imposition of US sanctions by the Trump administration would aggravate tensions, and Washington should instead be seeking dialogue with Tehran, the agencies quoted him as saying.
Kremlin spokesman Dmitry Peskov also said on Monday that new sanctions on Iran are illegal.
Speaking on a regular media call, Peskov declined to say what measures Russia might adopt to counteract the US sanctions.