PRAGUE - The two parts of what used to be Czechoslovakia took European Union centre-stage Thursday as the Czech Republic assumed the EU presidency and Slovakia became the 16th member state to embrace the euro.

The EU presidency "means you are responsible for the world," Vaclav Havel, the last president of the federation that split amicably in 1993, said on the public-service Czech Television Thursday, pointing at two crises that have forced the Czech government to act fast.

While the threat of disrupted gas supplies due to a row over payments for gas between Russia and Ukraine creates a domestic challenge, one of the Czechs' first diplomatic moves will be to send an EU delegation to the Middle East to try and broker a peace deal between Israel and Hamas, Czech Prime Minister Mirek Topolanek said Thursday.

"We will organise an EU mission led by (Foreign Minister) Karel Schwarzenberg," he said.

Schwarzenberg's delegation -- including French and Swedish counterparts Bernard Kouchner and Carl Bildt, the EU foreign policy chief Javier Solana and external relations commissioner Benita Ferrero-Waldner -- will visit Cairo, Tel Aviv, Ramallah and Amman.

Their trip overlaps with one by French President Nicolas Sarkozy, free from his six months at the EU helm, to the region.

Topolanek said it was up to the European Union to "take the initiative" as it was impossible to "count on the US" at this time, referring to the political hiatus awaiting George W. Bush's formal handover of power to president-elect Barack Obama on January 20.

"You see, the presidency is no formality. The old year did not finish yet and we were already tackling two crises," he added.

In New Year's day remarks to the nation, President Vaclav Klaus, an outspoken eurosceptic who has previously dismissed the EU presidency as "unimportant," adopted a more respectful tone.

"We will gain a certain opportunity to influence the operation of this major institution. It is in our interest to succeed in this role as best we can," said Klaus.

The Czech Republic -- with Ireland, the last country holding out -- has yet to ratify the bloc's Lisbon Treaty, and Klaus suggested political leverage could be gleaned from that status.

While Czech Television reported that 20 percent of Czechs did not know their country was taking the EU presidency, citing a poll carried out by the STEM agency before Christmas, Slovaks could hardly have missed the euro switch.

Neither Klaus nor Topolanek appeared in public to celebrate the presidency on Wednesday, in stark contrast to Slovak politicians who made a big show of their euro party.

"The 16 years of an independent Slovak Republic have been a success story," Slovak Prime Minister Robert Fico said triumphantly before withdrawing 100 euros (139 dollars) from a cash machine in the parliament building.

In Slovakia's capital Bratislava, some 100,000 people gathered in its main square on Wednesday night.

"If someone is to take merit for the euro, it's the Slovak people who work hard for wages that are very remote from the level in advanced EU countries," Fico said on the Czech Television Thursday.

On Thursday, the Slovak central bank confirmed the switch to the single European currency, coinciding with the euro's 10th anniversary, had gone smoothly.

"At the moment, 96 percent of 2,258 cash mashines in Slovakia are working," National Bank of Slovakia governor Ivan Sramko told a press conference Thursday afternoon.

On Wednesday, the difference between the Czech sceptics and the euro-happy Slovaks showed even in the streets.

"I'm happy we have the koruna," said Milos, a Czech man in his thirties, declining to give his surname. "The euro will hurt the poorer Slovaks," he added, walking down a Prague street.

"I feel a step ahead of the Czech Republic. They are more cautious, but we are the first," said Katarina Benczova, 28, in Bratislava.