SUNDAY TIMES WEB DESK:Accusations of ties involving Russia are extremely sensitive in Ukraine which has battled against Moscow-backed separatists since 2014, in a conflict that has claimed some 13,000 lives.

Ukrainians are due to elect a president on March 31, five years after a pro-Western popular uprising ousted a Kremlin-backed regime, Moscow annexed Crimea and war erupted between Kiev and pro-Moscow rebels in the east of the ex-Soviet country.

On Monday, an independent media outlet aired a report alleging that people close to Poroshenko had smuggled parts for military equipment from Russia.

The investigation claimed that close Poroshenko associate Oleg Gladkovsky, who is first deputy secretary of the National Security and Defence Council, and his son have been directly involved in the scheme.

It claimed they enriched themselves by selling the smuggled parts to state defence companies at highly inflated prices.

The investigation claimed that the state-run defence company Ukroboronprom and its general director Pavlo Bukin were also involved in the scheme.

The state-run defence holding accused the investigative journalists of manipulating data, suggesting they might have received some information from criminal probes that had been opened in 2015-2016.

Poroshenko himself was not involved in the scheme but, the Kiev-based investigative journalism unit, claimed he had turned a blind eye to protect Gladkovsky.

There was no immediate reaction from Poroshenko but his spokesman Svyatoslav Tsegolko said the leader had tasked law enforcement agencies with conducting an “urgent probe” into the matter.

Gladkovsky said he was temporarily stepping down from the security council for the duration of the probe, a move Poroshenko approved.

“I categorically reject all allegations made in the so-called investigation,” Gladkovsky said in a statement.