Two investigators came to the presidential palace in Baabda on Friday evening to take the statement, the office said in a news release.
In its interim report last month, the UN commission said Lahoud was not a suspect in the 14 February truck bombing that killed al-Hariri and 22 others on a Beirut street.
But it said a suspect made a call to the president's phone minutes before the blast.
"The president informed [the investigators] of the accurate information pertaining to what has been reported about phone calls to the presidential palace before and after the crime, in addition to rumours relating to the crime that were carried by the media," said the presidential statement.
UN investigators questioned Lahoud, a staunch ally of Damascus, on Friday as part of their inquiry.
One suspect phoned Lahoud (R)
just before al-Hariri's (L) death
According to their investigation, one of the suspects had contacted Lahoud shortly before the assassination.
Lahoud said Ahmad al-Alali, a leader of the charity association al-Ahbash, called the presidential palace shortly before the explosion, presidential sources told Aljazeera.
Syria proposes venues
Syria proposed Cairo, Vienna and Geneva as venues for UN investigators to question six Syrian officials in an investigation into al-Hariri's death, a Syrian official said on Saturday.
The UN investigating team led by German prosecutor Detlev Mehlis had requested to interview the Syrian officials in the Lebanese capital, Beirut, where al-Hariri was killed.
The UN investigation has implicated senior Syrian and Lebanese officials in al-Hariri's killing. The six that Mehlis's team want to interview include Syrian President Bashar al-Assad's powerful brother-in-law Assef Shawkat.
Officials close to the UN investigation said the investigators asked the president about communications and the chain of command in his office.
Lebanese political sources told Aljazeera that the meeting lasted six hours.
Four Lebanese generals are under arrest and charged with al-Hariri's murder after the UN commission named them as suspects. One of the generals is the commander of the presidential guard and two others are close to Lahoud.