"Hopefully end of the year or early next year, we can get a decision on who we can actually charge in court," Liow told reporters at an MH17 memorial service in Putrajaya, Malaysia's administrative capital on Thursday, Reuters said.
About 90 family members of 43 Malaysians killed in the crash attended the service, where they were briefed on the latest developments in the investigation.
Read alsoUkraine, the Netherlands sign deal on MH17 probe jurisdictionThe Boeing 777 was shot down over eastern Ukrainian territory held by pro-Russia separatists fighting Ukrainian government forces, by a Russian-made Buk missile, the Dutch Safety Board concluded in an October 2015 report.
All 298 people on board, most of them Dutch, were killed.
The Netherlands foreign ministry announced last week that any suspects identified in bringing down the aircraft will be tried in a Dutch court and under Dutch law.
A Dutch-led team of investigators from Australia, Belgium, Malaysia, and Ukraine, concluded in September that the rocket was fired from territory in eastern Ukraine held by pro-Russian separatists.
That finding contradicts Russia's suggestion that the aircraft was brought down by Ukraine's military, not the separatists.
Authorities urged the people responsible for launching the Buk missile to come forward, Liow said, adding that the investigators' conclusions were sound.
Read alsoDutch journalists indirectly confirm place of residence of Russian officer involved in MH17 tragedy (Video)"We are confident that we will be able to identify the criminals responsible and that we will be able to bring them to court," he said.
Md Salim Sarmo, 68, whose son was on board MH17, said he had been waiting for justice.
"We were told that it's just a matter of time before they can be brought to justice ... this is a decision that we've been waiting for," he said.
Victims of the disaster came from 17 countries, including 196 Dutch citizens.