The two leaders had lunch together in RomeUS President George W Bush has said a plan for Kosovo's UN-backed independence should take effect now, despite Russian and Serbian opposition.
Mr Bush was speaking after holding talks with the Italian Prime Minister Romano Prodi, during a visit to Rome.
Mr Bush said he discussed Kosovo with Russian President Vladimir Putin during the G8 summit, and it was "time to bring this issue to its head"
Earlier Mr Bush had his first audience with Pope Benedict XVI.
The Pope raised his concerns about the plight of Christians in Iraq, and expressed hopes of a "regional and negotiated solution to the conflicts that afflict" the Middle East, the Vatican said.
Mr Bush will be continuing to Albania on the next leg of his European tour, which has already taken him to the G8 summit in Germany and Poland.
The G8 summit failed to reach consensus over Kosovo, in the face of strong opposition from Russia to independence for the province, which is still part of Serbia.
UN Special Envoy Martti Ahtisaari put forward a blueprint for Kosovan independence in April.
"It's time to move the Ahtisaari plan forward," Mr Bush said.
He also discussed the situation in Lebanon with the Italian prime minister.
"It's very important that foreign influences like that of Syria not be continually disrupting the Siniora government," said Mr Bush.
Visiting the Vatican earlier in the day, Mr Bush and the Pope shook hands and posed for photographs ahead of talks in Pope Benedict XVI's private library.
President Bush said the two had discussed the situation in Iraq.
"He was concerned that the society that was evolving would not tolerate the Christian religion, " said Mr Bush.
"He's worrisome about the Christians inside Iraq being mistreated by the Muslim majority."
The Vatican said that "the Middle East, the Israeli-Palestinian question and Lebanon" were other topics at the talks.
The BBC's David Willey, in Rome, says President Bush told the Pope about his plans for increasing American aid to Africa and particularly for increasing help to Aids sufferers.
President Bush said talking to the Pope had been a "moving experience."
"I was talking to a very smart, loving man," said the US president. Fair use from BBC.