Agencies - Russia says it has bolstered its forces along the border with Ukraine as a precaution against the unrest in the country spilling over into Russia.The Kremlin previously claimed that troops were in the area on routine exercises, but their presence sparked accusations that it was about to march into troubled east Ukraine. The largely Russian-speaking region has been gripped by a separatist insurgency following the overthrow of Ukraine’s pro-Russian former president following mass protests in Kiev. A Ukrainian government ‘anti-terrorist operation’ to clear the insurgents this week ended in farce, with troops apparently switching sides and giving up their armoured vehicles to the militants. Kremlin spokesman Dmitry Peskov today insisted Russia had reinforced its battalions near the Ukrainian borders to protect Russian territory.Western intelligence sources say that an estimated 40,000 Russian troops are now deployed in areas bordering Ukraine, raising fears of an invasion into the east of the country which has a large Russian-speaking population. ‘We have forces in the region of the Ukrainian border,’ Mr Peskov said today on Russian television. ‘Some of these forces are based there permanently, others are there to reinforce, against the backdrop of what is happening in Ukraine itself.’ He added: ‘Forgive me but, Ukraine is a country where there has just been a military coup, so naturally any country is going to take particular precautionary measures in terms of ensuring its security.’He said as a sovereign state, Russia was free to deploy troops anywhere on its territory without restrictions. He denied allegations that the Russian military was interfering in events inside Ukrainian territory. Those assertion were, said Mr Peskov, ‘completely wrong.’ Western diplomats have accused Russia of helping to foment the uprising in east Ukraine in anticipation of a crackdown it can use as a pretext to invade. Last month the sudden appearance of heavily armed, masked men in Crimea preceded that province’s sudden secession from Ukraine and subsequent referendum vote to affiliate to the Russian Federation.After weeks of denials, Russian President Vladimir Putin this week admitted that at least some of those men were Russian soldiers, as had been widely suspected. oday a peace deal thrashed out between Russia, Ukraine, the EU and the USaiming to end east Ukraine’s insurgency was teetering on the brink of collapse after militants ignored calls to lay down their arms. Leaders of the gunmen who have taken over official buildings in and around the Donetsk region demanded that the leaders of the Kiev uprising which overthrew former president Viktor Yanukovych first quit their government posts.Moscow yesterday renewed its insistence that it has no control over the militants - a denial that the Western allies of the new Ukrainian government do not accept. The USwarned of heavier economic sanctions than those already imposed over Crimea if Moscow failed to uphold the Geneva deal - or if it moved to send troops massed on the border into Ukraine.‘We believe that Russia has considerable influence over the actions of those who have been engaged in destabilising activities in eastern Ukraine,’ national security adviser Susan Rice said. ‘If we don’t see action commensurate with the commitments that Russia has made yesterday in Geneva ... then obviously we’ve been very clear that we and our European partners remain ready to impose additional costs on Russia. ‘Those costs and sanctions could include targeting very significant sectors of the Russian economy.’President Vladimir Putin’s spokesman hit back, while voicing scepticism - of a kind also heard from the Ukrainian government - about how useful the cautiously worded Geneva pact would be. ‘You can’t treat Russia like a guilty schoolboy,’ said Dmitry Peskov. ‘That kind of language is unacceptable.’The Russian Foreign Ministry said: ‘The Americans are once again stubbornly trying to whitewash the actions of the Kiev authorities, who have embarked on a course of violently suppressing protesters in the southeast who are expressing their legitimate indignation over the infringements of their rights.’Later in the day, USSecretary of State John Kerry called Russian Foreign Minister Sergei Lavrov and urged ‘full and immediate compliance’ with the Geneva agreement, a senior State Department official said. ‘He made clear that the next few days would be a pivotal period for all sides to implement the statement’s provisions, particularly that all illegal armed groups must be disarmed and all illegally seized buildings must be returned to legitimate owners,’ the official said.