The last major poll published Wednesday ahead of Ukraine's parliamentary election showed President Petro Poroshenko's party seizing up to a third of seats but reliant on help from nationalist parties to form a ruling coalition.

The Kiev-based Foundation for Democratic Initiatives said just over 30 percent of respondents who had made up their minds and intended to vote in Sunday's ballot preferred the pro-Western Petro Poroshenko Bloc.

Ukraine's Western-backed leadership vowed on Tuesday to conduct a full inquiry into allegations the army used banned "cluster bombs" in its push against pro-Russian insurgents in the separatist east.

Human Rights Watch has published an investigation conducted jointly with The New York Times identifying 12 incidents in which the highly-imprecise munitions killed six people -- including a Swiss aid worker -- in and around the rebel-held city of Donetsk earlier this month.

The CEO of French oil giant Total, Christophe de Margerie, died in a plane crash at a Moscow airport late Monday when the private jet he was using struck a snowplough on takeoff.

Russian investigators said Tuesday the driver of the snow-clearing machine was drunk and that his actions, along with "an error by air traffic controllers", appeared to be to blame for the crash.

Amnesty International charged Monday that Kiev's forces fighting in eastern Ukraine may be guilty of extrajudicial killings, as well as the pro-Russian rebels.

The rights group found evidence of deliberate killings "attributable to both sides, but not on the scale reported by Russian media and authorities," the rights group said in a report.

War-weary Ukrainians pick a powerful new parliament next Sunday set to be dominated by pro-Western and nationalist forces who will determine if President Petro Poroshenko can make peace with the Kremlin while holding on to the separatist east.

But it will be a vote held on a war footing in which millions of ethnic Russians in Ukraine will not be able to cast ballots because their lands have been either annexed by the Kremlin or seized by pro-Moscow militants.

The Swedish armed forces stepped up a military operation off the coast of Stockholm on Saturday where they were investigating a report of "foreign underwater activity."

More than 200 men, Swedish stealth ships, minesweepers and helicopters have been searching an area of the Baltic Sea about 50 kilometers (30 miles) east of the Swedish capital since Friday evening, following a tip-off from what the military called a "credible source."

Two Ukrainian soldiers have been killed in combat with pro-Russian rebels in east Ukraine, Kiev's military said Saturday, as violence rocked a truce after talks between Kiev and Moscow ended without a breakthrough.

"Two Ukrainian soldiers were killed over the last day, three were injured," said spokesman Volodymyr Polyovy.

Russian President Vladimir Putin was cooperative and constructive when asked for his help in allowing investigators access to the MH17 crash site in Ukraine, Australian Foreign Minister Julie Bishop said Saturday.

Bishop met the Russian leader on the sidelines of the Asia-Europe Meeting, just days after Australian Prime Minister Tony Abbott warned he would confront Putin over the shooting down of the plane at a G20 meet next month.

Ukraine and Russia both signaled progress towards settling their festering row over gas Friday, raising hopes of an EU-backed resolution of the broader conflict embroiling the Soviet-era allies.

Russian President Vladimir Putin met his Ukrainian counterpart three times in the space of ten hours in Milan Friday, twice in the company of various European Union leaders then, finally, in their first private meeting since late August.

Russian President Vladimir Putin said Friday he had had "good" talks about the Ukraine crisis with his Ukrainian counterpart Petro Poroshenko and EU leaders in Milan.

Asked by journalists how the talks had gone, Putin said simply they were "good", the state news agency TASS reported.