Ukraine’s President Petro Poroshenko has declared a ceasefire within a 40-kilometer zone around the crash site of a Malaysian passenger plane in the eastern part of the country.

“I have given the order: right away, Ukrainian servicemen must not hold operations and must not open fire within the 40km radius of the site of the tragedy,” Poroshenko told reporters during a visit to the Malaysian embassy in Kiev on Monday.

The Ukrainian president also noted that he had given instructions to invite Russian experts to join a probe into the place of the crash in the volatile eastern Donetsk region.

Meanwhile, Andrei Purgin, deputy Prime Minister of the self-proclaimed Donetsk People's Republic (DPR) said that the DPR forces had “guaranteed security at the site from day one after the crash.”

The remarks come amid reports that four people were killed in Monday’s clashes between Ukrainian troops and pro-Russia activists near Donetsk’s railway station and its airport.

In a statement on its website, the Donetsk city council asked residents in the area to stay indoors, saying, "It is dangerous near the railway station.”

SS