By Adrian Croft and Jana Mlcochova
BRUSSELS/PRAGUE (Reuters) - NATO and European Union leaders upbraided Georgian Prime Minister Bidzina Ivanishvili on Monday over the arrest of political opponents as he visited Brussels to try to bolster ties with the West.
Ivanishvili, a billionaire whose coalition won a parliamentary election last month, has been accused by opponents of being too close to Russia, but signaled by making Brussels his first foreign destination that relations with the West were his priority.
Fears of political score-settling have been raised by the detention of a former interior minister and two army commanders on suspicion of insulting servicemen a year ago.
They have not been charged but could be jailed for up to eight years if found guilty of abuse of power. The commanders have been freed on bail but the ex-minister is still being held.
"I'm extremely concerned about the development we have seen since (the elections), not least related to recent arrests of political opponents in Georgia," NATO Secretary-General Anders Fogh Rasmussen said during a visit to Prague.
"It's for the legal system, the judicial system, in Georgia to sort out these cases. But of course it's important that such trials are not undermined by political interference."
The 56-year-old Ivanishvili, who made his fortune mainly in Russia, has vowed to take action against former officials suspected of wrongdoing. He has also said he will be better at building bridges with Moscow than with the West.
"We will do our best to speed up and accelerate our aspiration of achieving our ultimate goal, which is integration into the European family," he told reporters after talks with European Commission President Jose Manuel Barroso and European Council President Herman van Rompuy.
Barroso said democracy was about more than elections.
"Situations of selective justice should be avoided as they could harm the country's image abroad and weaken the rule of law," he said. "I've addressed this issue to the prime minister and he responded to me in a very concrete way."
Ivanishvili did not respond to the criticism directly before the media but said he had told Barroso that his government would do its best to protect human rights and advance democracy.
A European Commission source said Ivanishvili and his ministers were "trying to portray themselves as very pro-European and pro-reform".
Ivanishvili is due to meet Rasmussen on Wednesday.
Ivanishvili's election victory in October ended the nine-year dominance of Georgia by President Mikheil Saakashvili, who had in 2008 secured a promise of NATO membership.
The country of 4.5 million is a transit country for Caspian Sea oil and gas exports to Europe, but has been a focus of tensions between Russia and the West.
Months after gaining its NATO promise, Georgia increased qualms in Europe and NATO about letting it into Europe's mainstream by going to war with Russia over the breakaway regions of South Ossetia and Abkhazia, which Russia says are now independent states.
The EU is pushing Georgia to make reforms in many areas, including media freedom, the justice system and labor rights.
Ivanishvili and the EU leaders discussed progress in negotiations on a cooperation treaty between Georgia and the EU, including talks on a "deep and comprehensive" free trade area.
Barroso said he hoped the trade negotiations could be completed before a planned summit of EU and eastern European countries in Lithuania in late 2013, although that depended on the pace of trade reforms in Georgia.
(Additional reporting by Jan Lopatka in Prague, Sebastian Moffett in Brussels, Margarita Antidze in Tbilisi; Editing by Kevin Liffey)