BRUSSELS (Reuters) - The European Union scrambled to get a call with Ukraine’s president-elect Volodymyr Zelenskiy on Monday as Western powers wondered whether the TV comic would heed their urgings to stick with reforms that they hope can anchor the country beyond the grip of Russia.

Ukrainian presidential candidate Volodymyr Zelenskiy and his wife Olena react following the announcement of the first exit poll in a presidential election at his campaign headquarters in Kiev, Ukraine April 21, 2019. REUTERS/Valentyn Ogirenko

EU institutional leaders Donald Tusk and Jean-Claude Juncker wrote jointly to congratulate the 41-year-old political novice on an easy win over Petro Poroshenko, for five years the West’s champion in Kiev. But they also stressed that they are counting on more democratic reforms and fighting corruption.

Highlighting Sunday’s smoothly run vote as a “major achievement” after five years in which the EU has pumped cash into Ukraine and borne the cost of economic sanctions on Moscow, the respective presidents of the European Council and Commission urged Zelenskiy to seek continuity.

“Much remains to be accomplished to fully realize the peaceful, democratic and prosperous Ukraine that its citizens have called for,” Tusk and Juncker wrote.

“You can count on the EU’s strong support to Ukraine’s reform path, including consolidating the rule of law, fighting corruption, maintaining macrofinancial stability and pursuing the essential reform of the energy sector.”

With Europe and North America taking an Easter holiday, there was little other comment on the second-round vote result that had been widely forecast by recent opinion polls. Diplomats and officials in Brussels working with both the European Union and NATO said Zelenskiy was still very much an unknown quantity for Western governments.

“Very few from the European elite -- if any -- know him,” said a senior EU diplomat in Brussels.

Another called Zelenskiy’s task “quite challenging” in managing appointments and parliamentary elections, as well as in his relations with billionaire power-brokers. Those included Ihor Kolomoisky, owner of the TV channel that broadcasts his show. However, the diplomat said he felt some “cautious optimism”.

EU officials had been quietly in contact with people close to Zelenskiy since he romped home ahead of Poroshenko in the first round, EU sources told Reuters. Tusk and Juncker proposed a meeting as soon as possible and officials were trying to set up phone contact within the coming hours. There were also tentative plans for a formal EU-Ukraine summit in July.

German Chancellor Angela Merkel said in a letter to the president-elect, who is expected to take office next month, that she looked forward to hosting him for talks in Berlin soon.

“The German government will also in the future continue to support Ukraine’s right to sovereignty and territorial integrity,” Merkel wrote.

‘WE NEED TO GET HIM ON THE PHONE’

The European Union has invested heavily, in both economic and political terms, in Ukraine, seeing it as a potential model for other post-communist neighbors and a bulwark against a Russia seen as a growing threat, especially by the EU member states that spent decades under the control of Moscow.

But the 28-member bloc has also grown frustrated with continued corruption and democratic failings in Ukraine.

One senior EU official told Reuters: “We see the process as a win for Ukrainian democracy and we are eager to work with him (Zelenskiy) on reforms. But he remains an unknown quantity.

“We need to get him on the phone, set up meetings, get our message across about the seriousness of the need for reforms and our support but only on the basis of reforms. Clearly it’s a rebuke to Poroshenko, but the same reforms of the economy, against corruption are still crucial.”

A second senior EU official also stressed that Brussels saw Zelenskiy as having benefited from disappointment with Poroshenko. And while contacts during the campaign meant that Zelenskiy was not a total unknown to at least some EU officials, the official conceded that “we don’t have a very clear idea of his ideas beyond what he has said in the campaign”.

Those campaign statements included maintaining a broadly pro-Western course, though Zelenskiy said rather less than Poroshenko about one day joining the EU and NATO -- neither of which particularly appeal to Western states.

NATO Secretary-General Jens Stoltenberg tweeted his congratulations, adding cautiously: “Ukraine is a valued NATO partner and we look forward to continuing our cooperation.”

A European diplomat working with NATO in Brussels said: “We congratulate him -- but we will need to analyze who he is.”

Tusk and Juncker said further implementing Kiev’s trade and political pact with the EU could provide “crucial” help.

That deal, seen by the Kremlin as shifting the biggest of its Soviet-era satellites toward the West, was a factor in the events that culminated with pro-EU leaders installed in Kiev, Russia’s seizure of the Crimea peninsula in 2014 and pro-Kremlin separatists taking over Russian-speaking eastern Ukraine.