Gillett and Hicks, through their Kop Football vehicle, said on Tuesday they would pay 5,000 pounds per Liverpool share and the total value of the deal, including debt, was 219 million pounds.
Billionaire Hicks is the owner of the Texas Rangers major league baseball team and the Dallas Stars NHL franchise, while Gillett owns NHL's Montreal Canadiens.
The pair held a news conference on Tuesday to present themselves to supporters in a bid to avoid a repeat of the negative fan reaction when rival US sports tycoon Malcolm Glazer completed his buy out of Manchester United in 2005.
The American duo will act as co-chairmen of the 2005 European champions with each having a son on the board. Former owner David Moores has been made honorary life president.
"We respect the heritage and legacy of this franchise," Gillett said. "Our job is to be custodians of the franchise and add to the lustre, not detract from it.
"Owning this club is not about making money for us. It's about winning, passion and respect of the traditions and history."
Gillett and Hicks said they had not built up debt against the club to buy the five-times European Cup winners and would provide money for manager Rafael Benitez to buy players.
"We will not put a budget on what we will provide," Hicks said. "We will let Rafael Benitez and (Chief Executive) Rick Parry bring us their plans and then we will do what we can to make it happen."
The new owners did say they would consider selling the naming rights of the proposed new stadium they intend to finance.
NEW STADIUM
Work will start on the new 60,000-seat stadium, situated in Stanley Park near their existing Anfield ground, within 60 days. Gillett denied he had ever been interested in the controversial idea of ground sharing with city rivals Everton.
"If the naming rights are worth one good player a year in the transfer market, we will seriously consider the option," Gillett said.
Parry said Gillett's persistence was behind the club's decision to halt talks with rival bidders Dubai Investment Capital (DIC) last week.
"Last November was a finally balanced decision when we went with DIC," he said. "But things were taking longer with DIC than expected. We thought things would be wrapped up by Christmas."
"We have no doubts we have made the right decision."
Liverpool, who are FA Cup holders and last won their domestic league in 1990, have been seeking an injection of cash for three years to help challenge for top honours and fund a new stadium.
The 18-times league champions lie third in the Premier League table with 50 points from 26 games. Manchester United lead on 63 points while Chelsea are second with 57.
The deal follows a string of similar takeovers of English football clubs by wealthy individuals, with Russian billionaire Roman Abramovich buying Chelsea in 2003, Glazer taking over Manchester United and fellow American Randy Lerner buying Aston Villa.
The deal had been delayed earlier in the day when a computer failure stopped vital paperwork being transmitted to London for three hours.
(additional reporting by Sonia Oxley, Marc Jones, Mark Potter and Dan Lalor in London)
