UNITED NATIONS, Dec. 17 (Xinhua) -- The UN envoy for South Sudan on Tuesday urged the country's leaders to show political will toward formation of a transitional government by the extended deadline as pessimism grows on its peace process.

David Shearer, special representative of the secretary-general for South Sudan, told the Security Council that "the choice to twice delay a transitional government has dampened initial hopes, eroded trust and confidence and caused people to suspect that political will between parties is waning."

South Sudan President Salva Kiir and opposition leader Riek Machar have twice extended the deadline for establishing a unity government, which is set out in a revitalized peace agreement the two parties signed in 2018, to February 2020, due to lack of progress in some key areas.

"While this second extension has eased anxiety ... because it maintains the ceasefire, it has also disillusioned many citizens who feel more progress should have been made," said Shearer.

"Reasons can always be found for further delay ... But if the parties want to fully implement the agreement and form a new government, they can," he said, stressing "it comes down to political will."

He urged "measurable progress" to be made in key areas, including the reunification of forces and the issue of states and boundaries, to ensure the success of forming the government in time.

"In just two months, leaders will choose whether to form a transitional government," said Shearer, calling on the South Sudanese leaders to act to protect the ceasefire and move forward along the peace process.

Meanwhile, the UN envoy said South Sudan's ceasefire is currently holding, pointing to a steep decrease in civilian injuries, abductions and casualties.

"While sexual violence remains an abhorrent problem, the 295 victims recorded in 2019 are substantially fewer than the almost 1,300 reported in 2018," he added.