The value of Ukrainian President Petro Poroshenko's assets soared despite economic crisis and conflict while those of other tycoons shrank in an annual wealth list published Friday.

The 50-year-old Western-backed president's business empire ranges from chocolates to media holdings that still remain under his control.

Friday's independent Novoye Vremya weekly showed the Ukrainian leader -- often criticised for failing to curb the political powers of fellow tycoons -- ranked as the country's sixth-richest man.

His assets reportedly rose by 20 percent to $979 million (889 million euros) -- barely supporting his claim of no longer being a billionaire.

Poroshenko retains control of a top TV channel and has failed to follow through on his promise to sell off his Roshen chocolate empire due to a lack of foreign interest and a dearth of rich-enough investors in Ukraine itself.

The president's official spokesman did not pick up his phone when contacted repeatedly by AFP.

"Poroshenko's (wealth) rose thanks to the rise in value of his candy business that -- even in the midst of the deepest of crises -- is developing quickly, building new capacities and conquering new markets," the weekly said.

The wealth list is topped by the nationally renowned metals magnate Rinat Akhmetov

Tthe 49-year-old is a controversial figure accused by some Ukrainian media of impeding Poroshenko's efforts to halt the 18-month war in the pro-Russian east.

Novoye Vremya said Akhmetov's fortunes had plunged by 56 percent to $4.5 billion due in a part to the sharp recent fall in global commodity prices.

Poroshenko's sworn political foe and banking giant Igor Kolomoyskiy came in third with a fortune estimated at $1.9 billion.

The 52-year-old grey-bearded and fiercely outspoken figure finds himself in the peculiar position of being at odds with both Kiev and Moscow.

Russia's state media accuse him of funding Ukrainian neo-Nazi combat units that commit grave crimes in the separatist east.

Poroshenko's fight against Kolomoyskiy began with efforts to strip him of his indirect control of a state-owned oil company and culminated in the businessman losing his seat as governor of the industrially important Dnipropetrovsk region in March.

Kolomoyskiy's wealth reportedly slipped by 17 percent due to the EU-neighbouring country's financial woes.

All the other names in the top 10 also suffered losses since the weekly conducted its study last year.

Ukraine's economy is on track to lose about 12 percent of its gross domestic product this year and only return to marginal growth should the eastern campaign end in 2016.