Syrian and Russian forces will deploy in northeast Syria to remove Kurdish YPG fighters and their weapons from the border with Turkey under a deal agreed on Tuesday.

The agreement follows a U.S.-brokered truce which expired on Tuesday and underlines the dizzying changes in Syria since U.S. President Donald Trump announced the withdrawal of American troops two weeks ago ahead of Turkey's cross-border offensive against the Kurds.

The Russia-Turkey agreement endorses the return of Syrian President Bashar al-Assad's forces to the border alongside Russian troops, replacing the Americans who had patrolled the region for years with their former Kurdish allies.

Under the pact between Russian President Vladimir Putin and Turkish President Tayyip Erdogan, the two countries said Russian military police and Syrian border guards would start removing the YPG 30 kilometers from the Turkish border on Wednesday.

"Starting 12:00 noon (0900 GMT) of October 23, 2019, Russian military police and Syrian border guards will enter the Syrian side of the Turkish-Syrian border, outside the area of Operation Peace Spring, to facilitate the removal of YPG (Kurdish People's Protection Units) elements and their weapons to the depth of 30 kilometers from the Turkish-Syrian border, which should be finalized in 150 hours," the document published on the Kremlin's website said.

"At that moment, joint Russian-Turkish patrols will start in the west and the east of the area of Operation Peace Spring with a depth of 10 kilometers, except Qamishli city," it added.

Both parties will take the necessary measures to prevent the infiltration of terrorism, the memorandum said.

Last week's U.S.-brokered deal was limited to the central part of the border strip between the Syrian towns of Tel Abyad and Ras al Ain.

Under the deal with Moscow, the length of border which the YPG would be required to pull back from is more than triple the size of the territory covered by the U.S.-Turkish accord.

U.S. Vice President Mike Pence received a letter from Kurdish-led Syrian Democratic Forces (SDF) commander Mazloum Kobani on Tuesday saying their forces had withdrawn "from the relevant area of operations" under that deal, Pence's spokeswoman Katie Waldman said.

However, before flying to Russia, Erdogan had said hundreds of Kurdish fighters remained near Syria's northeast border despite the truce demanding their withdrawal. Earlier he had said the fighting might resume if promises by Washington were not kept.

Moscow and Ankara hailed the deal as a triumph

After six hours of talks with Erdogan in Sochi, Putin expressed satisfaction at decisions he described as "very important, if not momentous, to resolve what is a pretty tense situation which has developed on the Syrian-Turkish border."

To achieve "lasting and long-term stabilization in Syria as a whole" is possible only subject to the sovereignty and territorial integrity of the country, Putin stated during the press conference following their talks.

"We share the concern of the Turkish side in connection with the increasing threat of terrorism and the growth of ethno-confessional contradictions in this region. In our opinion, these contradictions and separatist sentiments have been artificially fueled by outsiders recently," he noted.

Syria must be exempted from an illegal foreign military presence, said Putin.

Erdogan praised the agreement for stopping "the creation of any separatist manifestations" on the Syrian territories.

"Both Turkey and Russia, we will not allow this," the president said following talks with Putin.

Hours after the deal was announced, the Turkish defense ministry said that the United States had told Turkey the withdrawal of Kurdish militants was complete from the "safe zone" Ankara demands in northern Syria.

There was no need to initiate another operation outside the current area of operation at this stage, the ministry said in a statement.

According to Russian Foreign Minister Sergei Lavrov, the Turkish "Operation Peace Spring" military offensive is being stopped.

"The operation is canceled. Everything will depend on how the agreements are implemented, including on the withdrawal of weapons and the withdrawal of forces and means of the Kurdish units," Lavrov said in footage published by the Russian Foreign Ministry.

On October 9, Turkey launched a military offensive dubbed "Operation Peace Spring" in northern Syria bordering southern Turkey in an attempt to fight Kurdish forces, which are deemed by Ankara as separatists and terrorists.

A senior Turkish official described it as an "excellent" deal which would achieve Turkey's long-held goal of a border strip cleared of the YPG, which Ankara regards as a terrorist organization because of its links to insurgents inside Turkey.

Following the Turkish action, the Kurdish Autonomous Administration of North and East Syria said on October 13 that it had reached an agreement with the Syrian government, backed by Russia, allowing the Syrian army to assume control of some Kurdish-held areas to counter Turkey's military progress.

Syria supports Russia-Turkey memorandum

Syrian President Bashar al-Assad supported the Russia-Turkey memorandum reached, the Kremlin said Tuesday.

Putin informed al-Assad in a phone call about the provisions on actions in Syria following talks with Erdogan.

The main task is to restore the territorial integrity of Syria and to continue joint efforts for a political settlement of the situation, including work within the framework of the Constitutional Committee, said Putin.

The Syrian president thanked Putin and expressed his full support for the results of the work.

The Syrian border guards are ready to enter the Syrian-Turkish border together with the Russian military police, he said.

Mixed voices in the U.S.

U.S. Vice President Mike Pence voiced support for the establishment of the safe zone.

"We may well give the international community an opportunity to establish a safe zone between Turkey and the Kurdish population in Syria that will ensure peace and security," Pence told a Heritage Foundation gala in Washington.

The U.S. withdrawal from northern Syria has been criticized by U.S. lawmakers, including some of Trump's fellow Republicans, as a betrayal of Kurdish allies who have helped the United States fight Islamic State in Syria.

Earlier on Tuesday, Jim Jeffrey, the senior U.S. diplomat on Syria, dismissed the Sochi deal and questioned whether the Russians could get the YPG to leave the territory it covers.

"It's full of holes," he told a congressional hearing. "All I know it will stop the Turks from moving forward. Whether the Russians will ever live up to their commitment, which is very vague, to ... get the YPG out of their areas, I don't know."

China insists on political solution to Syria issue

China's position of a political solution to the Syria issue remains unchanged, Chinese State Councilor and Foreign Minister Wang Yi said in an interview with AFP during his visit in France on Monday.

"We do not support Turkey's use of force in Syria and hope to adhere to the principle of political settlement. At the same time, we are ready to join hands with all countries, including Turkey, to combat terrorism and to jointly address the risk of terrorist spillover."

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China insists on political solution to Syria issue: FM

(With input from Reuters, Xinhua)