Zelenskyy was welcomed by French President Emmanuel Macron ahead of a morning working session with G7 leaders to discuss the war.
The Ukraine talks come on the heels of US President Donald Trump's announcement of an agreement to end the three-and-a-half month US war against Iran.
Trump said he had good conversations on Sunday with both Zelenskiy and Russian President Vladimir Putin.
"Now that this (Iran) is finished, we're going to be focusing on that," he said at the G7 summit.
Macron said he'll seek to persuade Trump to continue supporting Ukraine and increase pressure on Russia to help reach a peace agreement.
Hours before the start of the G7 summit, Russia fired hundreds of drones and dozens of missiles at Ukraine's biggest cities in a barrage that killed 11 people and set fire to a religious landmark.
Trump has been frustrated by a lack of movement toward Ukraine-Russia resolution
European diplomats hope to convince Trump that previous US positions on possible terms of a deal were overly favourable towards Moscow, particularly now that Ukraine's drone incursions have put Russia on the defensive.
European Commission President Ursula von der Leyen told reporters that Ukraine was gaining ground and hitting targets deep inside Russia, whose "war economy has never been as weak".
Zelenskiy took part in the first session of the day dedicated to "Building peace in Ukraine" and may talk separately with Trump. He was also due to meet other G7 leaders individually.
With negotiations stalled, Zelenskiy is pushing for renewed momentum and a greater European role.
Zelenskiy offered to meet Putin at the G7 summit, but he said the Russian president was not ready for peace talks.
European leaders were also set to warn Trump that a superficial interim deal with Iran risks entrenching Tehran's nuclear and ballistic missile programs.
Macron said the priority was to ensure there is a "solid, serious agreement that is finalised".
He said Tuesday's working lunch would focus on the safe reopening of the Strait of Hormuz, including a possible Franco-British-led maritime mission.
It would also seek to identify alternative energy routes to bypass the waterway, which Iran has largely closed since shortly after it was attacked by the US and Israel at the end of February. Trump said the strait would be "completely open" on Friday.
Leaders from the United Arab Emirates, Qatar and Egypt were due to attend Tuesday's talks. They were not expected to get into detailed discussions on Iran's nuclear program, but to outline their expectations, diplomats said.
The interim deal should open a 60-day window for complex technical negotiations that would include the fate of Iran's stockpile of highly enriched uranium and the lifting of international sanctions.
However, European allies fear an inexperienced US negotiating team may fail to secure a robust nuclear agreement or address Iran's ballistic missile program in the next phase, potentially creating a prolonged standoff.
France, Britain and Germany want a role shaping the coming talks after being sidelined in recent months.
The three countries first engaged Iran on its nuclear program in 2003 and later worked with then-US president Barack Obama to secure a 2015 deal in exchange for sanctions relief. Trump is scornful of that accord, which he pulled the US out of during his first presidency.
with Reuters
