"The security situation is still very unstable," Pieter-Jaap Aalbersberg, head of the mission to repatriate the remains of the victims, told journalists in Kiev.
"We are not absolutely sure if we can reach the crash site with the whole team of experts in the near future, but we are more hopeful than we were yesterday," he said.
Aalbersberg said that investigators would try to get to the site Friday to "carry out limited searches at a few locations".
They were forced to make a 500-kilometre round-trip following the announcement of a one-day ceasefire across the region by Ukrainian forces.
The visit was the first time in nearly a week that international investigators had managed to make it to the site after being repeatedly thwarted by clashes between the Ukrainian army and rebel fighters.
An AFP crew following just a few minutes behind the international team heard bursts of shelling and saw black smoke rising from areas close to the crash site.