BRUSSELS, Nov. 24 - European Union leaders reaffirmed support for carrying out a 2014 pact on closer ties with Ukraine but cited "limitations" amid divisions over how far to go with a country mired in intractable corruption and conflict, Reuters reported.

Some in Ukraine feel the EU has not shown enough support in its confrontation with Russia and worry that promises by U.S. President-elect Donald Trump to mend Washington's relations with Moscow could be come at their expense.

On top of that, a provision to lift EU visas for Ukrainians is snagged and the Netherlands is struggling to work around a national referendum that rejected the EU's agreement on freeing up trade and building closer political ties with Kiev .

Three years after a pro-EU uprising overthrew the Moscow-allied leadership in Kiev, the mood was publicly upbeat at Thursday's Brussels gathering at which European Council President Donald Tusk spoke Ukrainian and exchanged jokes with Ukrainian President Petro Poroshenko at a joint news conference.

"You have many friends here, and I can promise you that you will not be left behind," Tusk said. "We also have our limitations, but we will continue in our efforts to fulfill your justified expectations.

" Ukraine 's success will be the success of all of Europe ."

But behind the official optimism, problems with the deal are mounting as many in the EU are unhappy with the pace of reform in Ukraine , especially in purging rampant graft, and some want to rehabilitate trade ties with major energy supplier Russia .

EU leaders told Poroshenko he must do more in rooting out graft, improving rule of law and liberalizing the economy.

Still, Tusk said he hoped Ukrainians would be granted visa-free travel to the EU - coveted by Kiev - by year-end.

But that is not certain as Germany and France have stalled the process, fearing an influx of Ukrainians could pressure the job market and stoke anti-foreigner feeling that has already hurt mainstream parties facing elections next year. (rt/ez)