Zelenskiy told reporters that the US and Ukrainian working groups would focus on bilateral documents and discuss a wide-ranging drone deal during the meeting on Saturday.
Ukraine, eager to capitalise on its expertise in defending against Russian drone attacks, is also working to finalise agreements with eight Middle Eastern countries as the US-Israeli war with Iran escalates, a source familiar with the matter said.
Zelenskiy told reporters Ukraine has deployed 228 specialists to help Middle Eastern countries with drone defence, and is working with Middle Eastern leaders to sign "serious agreements" but gave no details.
The talks in Miami were initially planned to include Russian negotiators and take place in Abu Dhabi, with a focus on finding a settlement to the four-year-old war sparked by Russia's full-scale invasion in February 2022.
The trilateral meeting in the United Arab Emirates was postponed after the outbreak of the Iran conflict on February 28.
The White House had no immediate comment on the weekend meeting.
The US negotiating team will be led by special envoy Steve Witkoff and Jared Kushner, Trump's son-in-law, the source said.
Zelenskiy told reporters that Ukraine was sending his chief of staff Kyrylo Budanov and his deputy, Serhiy Kyslytsia, as well as Davyd Arakhamia, the head of his parliamentary faction.
Ukraine and Russia have held two sets of US-brokered talks in the UAE this year and a round in Geneva last month.
Ukraine has expressed grave concerns to US officials about their moves to temporarily lift sanctions on Russia's oil sales as oil prices have surged during the Iran war, the source said, noting Russia had earned an extra $US10 billion ($A14 billion) in the conflict's first weeks.
Ukraine is also eager to keep purchasing US weapons despite the super power's focus on the Middle East and what it sees as a "moment of complete uncertainty," the source said.
"There were some disruptions at the beginning of the (Iran) operation but those were mitigated and we haven't seen any major decisions on repurposing the existing stocks or suspending the supply," the source said.
Ukraine has long asked for more PAC-3 missiles for its Patriot defence systems and is running short, the source said.
US and Ukrainian officials will meet again in Kyiv next week for the third meeting of the US-Ukraine Reconstruction Investment Fund, which has aimed to approve a first joint investment project by the end of March.
