The former president cut short a vacation in the Czech Republic to return to Kiev on Saturday, a day after his onetime interior minister Yury Kravchenko was found dead.
Kravchenko was due to answer prosecutors' questions over the 2000 killing of investigative reporter Georgy Gongadze on Friday.
Gongadze, who had been critical of Kuchma in articles in his internet newspaper Ukrainska Pravda, disappeared in September 2000 and his headless body was found two months later.
His gruesome death, which became a symbol of the corruption within Kuchma's government, sparked widespread opposition that eventually led to its downfall late last year, and is now threatening some of its most senior members.
Although prosecutors have not yet said whether they will summon Kuchma, many observers expect the former leader - who was implicated in the killing in recordings that his former bodyguard smuggled out of the country - to eventually be questioned.
"It's very likely that Kuchma will be questioned," Andriy Yermolayev, a political analyst, said.
The murder triggered widespread anger at the government that culminated in last year's "orange revolution" protests that brought to power opposition leader Viktor Yushchenko .
Yushchenko (R) says solving the
murder case is a priority
Yushchenko has made solving Gongadze's murder one of the top priorities of his administration.
Kuchma was implicated in the death after his former bodyguard Mykola Melnichenko released tapes that allegedly had recorded Kuchma, in between epithets, ordering Kravchenko to take care of the persistent investigative reporter.
Kuchma has repeatedly denied any wrongdoing and has called the tapes a fabrication. On Friday, he said he was innocent "before God, before the people and before my conscience".
Meanwhile, speculation swirled in Ukraine over whether Kravchenko, who was found dead with two shots to his head at his elite country home on the morning he was due to appear at the prosecutor's office, killed himself as police insist.
Police said Kravchenko died after shooting himself twice - first in the chin and then in the temple - and left a note laying the blame for the Gongadze murder on Kuchma.
"I am not guilty of anything," police have quoted the note as saying. "I have become a victim of political intrigues of president Kuchma and his entourage. I am leaving you with a clear conscience."
"It's very likely that Kuchma will be questioned"
But many observers have raised doubts over the official version.
Either Kravchenko ordered Gongadze's killing or "his death was in the interest of several people, particularly those who are really behind the killing who do not want to be held responsible for the crime," the Komsomolskaya Pravda newspaper wrote.
"Kravchenko was ready to carry out any order by Kuchma," Yermolayev said. "Kravchenko's death played towards the thesis that Kuchma commandeered and Kravchenko organized [the killing]."