Laporta, who was previously Barca president between 2003 and 2010, was voted in by club members last weekend but had to secure a ?125 million bank guarantee before being inaugurated.
Now in office, one of his first tasks is convincing Messi, who turns 34 in June, to extend his contract, which expires the same month, beyond the end of the season.
Messi, who wanted to leave last summer, voted in last Sunday's election and was seated in front of Laporta as he made his speech at Camp Nou on Wednesday in front of around 300 invitees.
"I will try to convince Leo to stay at the club," Laporta said, turning his attention towards Messi near the end of a 30-minute speech as the rest of the attendees clapped.
"Sorry Leo, but I will do my best, he knows it. We're going to try and convince him to stay because he's the best ever and, forgive me for this Leo, but I love you and Barca loves you, too.
"If this stadium was full, I'm sure you couldn't leave -- another issue caused by this damned pandemic! Whatever his decision, it will be fine, but we're going to try [and keep him]."
Addressing the coach, Laporta said: "Ronald, you have the board's confidence," Laporta added. "The team has improved and we have to get back to winning things.
"If we fix things financially, we will be competitive once again in the Champions League. We can win La Liga and the Copa del Rey this season."
