Federal division of Syria
530 people killed during first 23 days of Syria ceasefire: SOHR In Picture: Civil Defence members put out a fire that spread in an oil refinery in the town of Marat Numan in Idlib province, Syria Mar. 10, 2016.Reuters

The U.K.-based Syrian Observatory of Human Rights (SOHR) reportedly said Tuesday that 530 people died in the first 23 days of the ceasefire in Syria in areas where the peace agreement is applicable. The Syrian human rights watchdog also said that 1,279 people died in places where the ceasefire is not operational. 

Russia, which withdrew an air wing from Syria, had recently called on the U.S. to initiate punitive measures against violators of the ceasefire, adding that it would act unilaterally if action was not taken. The U.S. has, however, dismissed Russia's concerns and rejected the call for a meeting on the issue. The western country said that those concerns are already being dealt with.

"We have seen the media reports on alleged Russian concerns over ceasefire violations. Whoever is making such statements must be misinformed, because these issues have been discussed at length already, and continue to be discussed, in a constructive manner," a U.S. official told Reuters in Geneva Monday.

"If there is no reaction from the U.S. to our proposals [on the control of ceasefire], starting from March 22 Russia will unilaterally apply rules provisioned in the [cessation of hostilities] deal," the chief of the Russian General Staff's main operations department, Sergey Rudskoy, was quoted as saying by RT Monday.

The truce excludes the Islamic State of Iraq and Syria and al Qaeda-linked Nusra Front from its ambit. The two outlawed groups continue to attack the country even as the U.S.-led coalition and Russia counterattacked. U.N. peace envoy Staffan de Mistura was quoted as saying by Reuters that the future of the peace process may be in jeopardy due to an impasse on Syria President Bashar al Assad's future.

The "cessation in hostilities" was agreed on by multiple countries and came into place Feb. 27. The five-year long battle in the conflict-ridden country has killed 2,50,000 people and displaced millions.