Russia is deliberately fomenting disorder in Ukraine to disrupt the presidential elections in the former Soviet republic later this month, the British foreign secretary, William Hague, has said.

As the Russian foreign minister, Sergei Lavrov, said pro-Russia rebels in the east of the country should be included in talks on an equal basis to the government in Kiev, Hague accused Moscow of failing to take action to implement the Geneva accord.

Hague, who has been meeting civic and political leaders in Ukraine before elections on 25 May, denied that extremists were dominating the country. "The idea that some extremists have taken over here is far, far wide of the mark," he said, pointing out that he had met Mykhailo Dobkin, the presidential candidate of the former governing Party of the Regions. The foreign secretary said Dobkin wanted the elections to take place on 25 May and was opposed to any further annexation of Ukrainian territory by Russia.

The foreign secretary told BBC Radio 4's Today programme "They [Ukrainians] cannot be bullied out of having their elections by disorder that is deliberately fomented and co-ordinated from another country – in this case from Russia. They are entitled to have their democratic choice, to choose their own president. Hopefully that new president will be a unifying figure who can clear out corruption, who can set a good economic programme and who can bring about this de-escalation."

Hague was speaking after his German counterpart, Frank-Walter Steinmeier, warned that "we are not far from a military confrontation" amid an intensification of fighting in the south and east of Ukraine. Moscow called for rebels in control of much of the south and east to be included in talks on an equal basis.

The foreign secretary accused Moscow of disruptive behaviour amid fears that Russia is going out of its way to block the elections or to ensure they have little credibility in a disjointed country. He said of the Geneva accord agreed on 17 April: "Russia took not a single action, not one action we can identify to implement that agreement.

The foreign secretary added that the possibility of the permanent presence of larger numbers of Nato forces in eastern Europe should worry Russia. "It is moving forward in a way that should worry Russia in the long term … There will be Nato countries that increase their defence expenditure, that see a revitalised role for Nato. Yes, we will reduce our energy dependence on Russia in western European countries. We will exclude Russia from the G8 and the OECD. Taken over the next decade these events will have a major effect on Russia."

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