Malaysia and Ukraine are committed to find out the truth on the downing of Malaysia Airlines flight MH17 and bring the perpetrators to justice.

The pledge by Malaysia's Prime Minister Datuk Seri Najib Tun Razak and visiting Ukrainian President Petro Poroshenko was made in a joint press conference between both leaders here today after their bilateral meetings.

Datuk Seri Najib said Malaysia and Ukraine were waiting for the criminal investigation report, which is expected to be released at the end of this year.

He said after the report was published, five countries - Australia, Belgium, Malaysia, the Netherlands and Ukraine would meet again and agree on the next cause of action.

"This (meeting) is to ensure that justice can be served to those who are responsible for the incident and perpetrators for shooting down the civilian aircraft.

"With respect of the MH17, we are committed to whatever we can especially for the sake of the families who have lost their loved ones in that very tragic incident," Datuk Seri Najib said.

The Boeing B777 aircraft, with 298 people onboard including crew, was shot down over eastern Ukraine while traveling from Amsterdam to Kuala Lumpur on July 17, 2014.

Malaysia's Transport Minister Datuk Seri Liow Tiong Lai had on July 16 said Malaysia hoped to receive the preliminary conclusions on the forensic research report of flight MH17 by the Joint Investigation Team (JIT), which would also include the type of weapon used and other pertinent details.

Echoing similar sentiments, Poroshenko said Ukraine was also committed to the need to complete the investigations of the MH17 tragedy, and to ensure to engage all the possible ways to bring the perpetrators to justice.

"This is our way of paying tribute to the innocent lives and as well as our duty to the victims and their families.

"I want to use this opportunity to offer my sincere condolences to all the families who suffered a lot from the disastrous terrorist attack of MH17," he said.

Earlier, Datuk Seri Najib and Poroshenko witnessed the signing of two treaties and an agreement between the two countries on various fields.

Both governments had concluded an agreement for the avoidance of double taxation and the preventation of fiscal evasion with respect to taxes on income.

The agreement was signed by the Malaysian Foreign Minister Datuk Seri Anifah Aman and his counterpart Pavlo Klimkin. Both ministers also inked a treaty on extradition.

Meanwhile, Klimkin also signed the treaty on mutual legal assistance in criminal matters, with Malaysia, represented by Attorney General Tan Sri Apandi Ali.

Poroshenko, who arrived yesterday, is on a three-day official visit to Malaysia.