A Syrian ceasefire set to start at the weekend garnered another critical vote of support Wednesday, when Saudi Arabia's king confirmed his country's backing for the plan during a telephone conversation with Russian President Vladimir Putin.
King Salman ibn Abd al-Aziz "welcomed the achieved agreements and expressed readiness for mutual work with Russia to realize them," the Kremlin said in a statement.
Saudi Arabia has been a key backer of the Syrian opposition and rebel factions, whereas Russia supports Syrian President Bashar al-Assad, a longtime ally.
Earlier on Wednesday, the Kremlin announced in a separate statement that al-Assad had confirmed his support for the ceasefire during a telephone conversation with Putin. Al-Assad had already signaled his backing on Tuesday.
Al-Assad described the ceasefire as an "important step toward a political resolution" for Syria's civil war, the Kremlin said on its website.
Putin and al-Assad emphasized the necessity of continuing an "uncompromised fight" against UN-designated terrorist groups, such as Islamic State and al-Nusra Front, the Kremlin said.
The ceasefire, which will affect the government's military, foreign interventionist forces and certain rebel groups, is planned to come into force on Saturday at midnight (2200 GMT Friday).
The ceasefire was agreed earlier this week by Russia and the United States, which have intervened militarily in the conflict. However, it is unlikely to end all the fighting in Syria, as several key groups, such as the Islamic State militia organization, were not involved in the talks.
On Wednesday, the Kremlin's spokesman told reporters that the intervention has improved trust between Russia and the US.
"Collaboration to any degree leads to an increased level of mutual trust," spokesman Dmitry Peskov said in comments carried by the Interfax news agency.