Ukrainian President Volodymyr Zelenskiy speaks during talks with journalists in Kyiv, Ukraine, Thursday, Oct. 10, 2019. Ukrainian President is holding an all-day “media marathon” in a Kyiv food court amid growing questions about his actions as president. (AP Photo/Efrem Lukatsky)

KYIV, Ukraine (AP) — Ukrainian President Volodymyr Zelenskiy accused his predecessor on Thursday of fomenting protests to derail a peace process for the country's separatist-held east and said talks with Russia were the only way to end the five-year war there.

Zelenskiy told reporters that Petro Poroshenko, the incumbent leader he defeated in April, was "pushing" people to oppose the withdrawal of heavy weaponry in eastern Ukraine, where fighting against Russia-backed separatists has killed more than 13,000 people since 2014.

"He is against the pullback and he thinks that he can spearhead another Maidan," Zelenskiy said, referring to the square in the capital of Kyiv where protests in 2013 and 2014 ousted a pro-Russian government and eventually propelled Poroshenko into power.

"We want to end this war. I don't think the previous government had quite the same desire," Zelenskiy said during an all-day "media marathon" in a Kyiv food court.

Zelenskiy said he hoped his country's people would back his efforts to end the conflict with the separatists.

Last week, Ukraine, Russia and the separatists signed a tentative agreement on guidelines for a local election and a weapons withdrawal in the east to pave the way for a much-anticipated four-way summit with Russia, Germany and France.

Poroshenko and some nationalist groups have cast the move as a capitulation to Moscow, and several dozen far-right Ukrainian activists and veterans traveled to the east this week vowing to stop the disengagement. Zelenskiy accused both separatists and veterans of trying to spoil peace efforts.

"As long as different people from both sides who don't want the disengagement keeping coming there and do random shooting, there won't be any pullback," he said.

Zelenskiy emphasized that the weapons pullback was a key condition for holding the four-way summit, which has no date set yet.

The planned withdrawal of troops and weapons by both government forces and the separatists was to begin Monday but was delayed because of shelling from both sides. The pullback again failed in two locations in eastern Ukraine on Thursday, separatist officials said. In Kyiv, the military in charge of the operation in the east said one Ukrainian soldier died in shelling Thursday.

Ukrainian officials said a cease-fire must hold without violations for a week before they proceed with the weapons withdrawal.

Russian Foreign Minister Sergey Lavrov said Thursday he regretted the withdrawal hasn't happened and expressed suspicion that Ukraine might be looking to backtrack on the agreement.

France and Germany brokered a 2015 peace agreement that envisaged a broad autonomy for the separatist regions in eastern Ukraine and an amnesty for the rebels — the provisions that were never implemented because it was resented by many In Ukraine.

The 2015 deal signed in Minsk, Belarus, also stipulated that Ukraine regains full control of its border with Russia only after the rebel regions receive broad autonomy and elect local leaders and legislatures. Ukraine and the West say Russia has backed the rebels with troops and weapons and the border has served as a conduit for them.

Zelenskiy pushed for Ukraine to get back its control of the border before the vote. He noted Thursday that Ukraine expects monitors from the Organization for Security and Cooperation in Europe and international peacekeepers to help monitor the frontier.

"There must be Ukrainian police, the OSCE and peacekeepers on the border with Russia," he said.

Lavrov, meanwhile, warned that Moscow would oppose any attempt by Ukraine to revise the 2015 Minsk agreement.

"We would do everything not to allow it," he said.

Ukrainian President Volodymyr Zelenskiy talks with journalists in Kyiv, Ukraine, Thursday, Oct. 10, 2019. Ukrainian President is holding an all-day
In this handout photo provided by the Ukrainian Presidential Press Office ,Ukrainian President Volodymyr Zelenskiy sits inside a military helicopter as he visits an arm exhibition in Kyiv, Ukraine, Wednesday, Oct. 9, 2019. (Ukrainian Presidential Press Office via AP)
Ukrainian army veterans and volunteers wave the national flag at a checkpoint near the village of Zolote in the Luhansk region, Ukraine, Wednesday, Oct. 9, 2019.  Several dozen activists arrived on Wednesday in the area of a much anticipated pullback of heavy weaponry from both sides of the de facto border, saying that they would try to prevent it from happening. (AP Photo/Bohdan Kutepov)
In this handout photo provided by the Ukrainian Presidential Press Office, Ukrainian President Volodymyr Zelenskiy, right, sits inside a military helicopter as he visits an arm exhibition in Kyiv, Ukraine, Wednesday, Oct. 9, 2019. (Ukrainian Presidential Press Office via AP)
Ukrainian President Volodymyr Zelenskiy speaks during talks with journalists in Kyiv, Ukraine, Thursday, Oct. 10, 2019. Ukrainian President is holding an all-day “media marathon” in a Kyiv food court amid growing questions about his actions as president. (AP Photo/Efrem Lukatsky)
FILE - In this April 20, 2019, file photo, a Ukrainian serviceman guards a position near the front line as the conflict continues, in Marinka, Donetsk region, eastern Ukraine. Ukraine signed much-anticipated accords with separatists from the country's east, Russia and European monitors on Tuesday, Oct. 1, 2019, that agree a local election can be held in separatist-controlled territory, paving the way for peace talks with Moscow. (AP Photo/Evgeniy Maloletka, File)
Ukrainian President Volodymyr Zelenskiy speaks during talks with journalists in Kyiv, Ukraine, Thursday, Oct. 10, 2019. Ukrainian President is holding an all-day