* EU commissioner hopes physical flows possible by year-end
* Slovak link part of wider debate on energy security
BRUSSELS, March 18 (Reuters) - A reverse-flow pipeline deal to ship gas from Slovakia to Ukraine could be agreed before the end of April, European Energy Commissioner Guenther Oettinger said on Wednesday.
The Commission, the EU executive, has been pushing for months to reach an agreement on a link from Slovakia to shore up Ukraine's gas supplies and reduce its dependence on Russia.
Efforts have intensified as Russia's relations with both Ukraine and the European Union have hit a crisis over Russia's annexation of Ukraine's Crimea region.
"I'm quite optimistic we can come to agreement before the end of April," Oettinger told reporters, adding talks with Slovakia would continue next week.
Oettinger said he hoped work could begin on new infrastructure as soon as possible after a deal is achieved, with the aim of completing it before the end of the year in time for peak winter demand.
Following previous gas crises involving disruption of Russian gas supplies to Ukraine, a major transit route for Russian gas, the European Union has been working on improving security of supply.
It has already established reverse-flow pipelines to pump gas east as well as west through Hungary and Poland, but the more important link is the Slovakian pipeline, which Oettinger said had the potential to pump up to 10 billion cubic metres per year.
Oettinger was speaking in Brussels following talks with Ukraine's visiting Energy Minister Yuri Prodhan.
Further talks on Thursday and Friday involving the leaders of the 28 EU member states will focus on reducing the European Union's energy dependence on Russia and how much gas it could ship to Ukraine in the event of any supply disruption.
Ukraine is part of the European Union's energy community, which aims to develop energy links with neighbouring non-EU countries and create a more joined-up energy market across the region with greater cross-border trade.
Fellow former Soviet republic Georgia is also hoping to join the energy community and attended a second round of talks on membership in Brussels on Wednesday.
Deputy Georgian Energy Minister Irakli Khmaladze told Reuters he hoped to sign a deal to join the EU energy community at the end of May.
"Basically the agreement is there. We hope to a sign a protocol at the end of May," he said, although he added he needed approval from the Georgian parliament.
The European Commission said it did not have an immediate comment on when Georgia's membership talks would be complete. (Editing by Andrew Roche)