Ukraine crisis: Moscow 'to help free European observers'

Moscow says it will do all it can to bring about the release of European military observers detained in eastern Ukraine by pro-Russian separatists.

The assurance came as EU diplomats revealed they will meet on Monday to discuss new sanctions against Russia.

Earlier, the G7 group of economic powers agreed to intensify sanctions.

The West accuses Russia of leading a secessionist revolt in Ukraine's east, after it annexed Crimea last month. Moscow denies the allegations.

Rebel militia continue to occupy official buildings in a dozen eastern cities, defying the Ukrainian government in Kiev.

Russia has tens of thousands of troops deployed along its side of the border with Ukraine and has said it would act if its interests were threatened.

The US accused Russian jets of violating Ukraine's airspace on Friday in a further sign of escalation.

On Saturday, Russia's Foreign Minister Sergei Lavrov spoke by telephone with his German counterpart Frank-Walter Steinmeier about ways to defuse tension in Ukraine.

'Carrying maps'

Negotiators are trying to secure the release of eight international observers who were seized and accused of espionage by pro-Russia gunmen.

The observers were taking part in a mission linked to the Organisation for Security and Co-operation in Europe (OSCE).

Quoting German government sources, Reuters said an OSCE team was on its way to the region to try to secure their release.

'We believe that these people should be released as soon as possible,' Andrei Kelin, Russia's envoy to the OSCE, was quoted as saying.

'As an OSCE member, Russia will take all possible steps in this case,' he said.

The group - believed to be military observers from Germany, Denmark, Poland, Sweden and the Czech Republic - is being held, along with several Ukrainian army personnel by forces in the city of Sloviansk.

Pro-Russian leaders in Sloviansk confirmed their bus had been stopped near Sloviansk and said they were checking the identities of those on board.

The city's self-proclaimed mayor of Sloviansk, Vyacheslav Ponomaryov, said at least one passenger had been carrying maps showing separatist checkpoints in the area, which suggested 'their involvement in espionage'.

Last weekend, Mr Ponomaryov broadcast an appeal to President Putin asking for Russian troops to protect the city from 'fascists' after three of his men died in a gunfight.

Meanwhile, the G7 praised Ukraine for acting with restraint in dealing with the 'armed bands' that had occupied government buildings.

But the group, which includes the US, UK, Germany, Japan, France, Canada and Italy, condemned Russia's 'increasingly concerning rhetoric and ongoing threatening military manoeuvres'.

'Given the urgency of securing the opportunity for a successful and peaceful democratic vote next month in Ukraine's presidential elections, we have committed to act urgently to intensify targeted sanctions and measures to increase the costs of Russia's actions,' said the statement.

The US and EU already has assets freezes and travel bans in place target a number of Russian individuals and firms accused of playing a part in the annexation of Crimea.