Russian President Vladimir Putin has met Pope Benedict XVI for the first time during an official visit to Rome.
Vladimir Putin and the Pope spent 25 minutes in private talks
They discussed ways to improve relations between the Roman Catholic and Russian Orthodox Churches, dogged by long-standing differences.
The Vatican said the talks had been held in a "very positive atmosphere".
Mr Putin was also expected to discuss energy and security with Italian Prime Minister Romano Prodi in meetings on Tuesday night and Wednesday.
President Putin was said to have been in favour of a visit to Russia by Pope Benedict's predecessor, Pope John Paul II.
But the late Pope was never able to fulfil his ambition of seeing post-communist Russia.
Pope Benedict puts great emphasis on healing the churches' divisions and some say this is helping to mend the 1,000-year schism between Rome and the eastern Christian churches.
The Pope and Mr Putin held "cordial" private talks lasting about 25 minutes, Vatican officials said.
The pair spoke mostly in German - the Pope's native language and the one used by Mr Putin during his years working for the KGB in the former East Germany.
Mr Putin and Romano Prodi are likely to focus on energy matters
Speaking before they met, the Papal Nuncio to Moscow, Monsignor Antonio Mennini, said relations between the two churches were much improved.
But any talk of a meeting between Pope Benedict and the head of the Russian Orthodox Church, Patriarch Alexy II, has been ruled out.
Monsignor Mennini said Mr Putin was paying a secular visit to Italy and it was still premature to be talking about papal visits to Moscow.
The BBC's Christian Fraser in Rome says the focus of Mr Putin's trip will now turn to energy and security, as he meets Mr Prodi.
The two men are likely to discuss disagreements between Europe and Russia over major issues like Iran, Iraq and the Middle East, our correspondent says.
They will also talk energy, he says, since the Russian gas giant, Gazprom, signed a deal with the Italian energy company, ENI, in November which gives the Russian firm a foothold in southern Europe.
But while Mr Prodi is a supporter of closer economic ties, he is looking for assurances from Mr Putin that Russia will guarantee supply and will not use gas and oil to drive hard diplomatic agendas with its neighbours, as Moscow has been accused of doing in the past, our correspondent adds