Premier League leaders Liverpool have signed France international defender Mamadou Sakho and Portuguese centre-back Tiago Ilori, as the pair became the first confirmed permanent arrivals at a top English club on Monday's transfer deadline day.

The duo, who watched Liverpool's 1-0 league win over champions and arch-rivals Manchester United at Anfield on Sunday, signed their contracts after completing medicals at the Reds' Melwood training ground complex.

Their arrival at northwest side Liverpool meant Reds manager Brendan Rodgers had now signed seven players during the transfer window, the duo following Kolo Toure, Iago Aspas, Luis Alberto, Simon Mignolet and Aly Cissokho to Anfield.

Sakho played more than 200 games for Paris Saint-Germain, winning the French championship with the capital club having already helped PSG lift the 2010 Coupe de France and the 2008 Coupe de la Ligue.

However, the 23-year-old, capped 14 times by his country, has become the latest French player to opt for life in the Premier League.

"I'm delighted to be here," Sakho, who can operate in central defence or at left-back, told Liverpool's official website. "I'd like to thank everyone for the welcome.

"I came here because the project that is in place at Liverpool interests me. I'm really looking forward to playing my first game."

He added: "I know the Liverpool fans are fantastic and while I was in France, it was clear for me to see they are amongst the best in England."

Ilori, a 20-year-old London-born centre-back who has joined Liverpool from Portuguese giants Sporting Lisbon, was also delighted to be at Anfield.

"It feels great being a Liverpool player -- coming to the Premier League has always been a dream for me," Ilori said.

"I'm going to try to achieve everything I can. I want to play as much as possible and we'll see what the future holds," the 6ft 3in defender added. "I will give my all and try my best to help the team."

Ilori has played for several Portugal age group teams -- Under-18, Under-19 and Under-20 -- and played at Anfield for Sporting in the 2011-12 NextGen Series.

"I know the history of the club and the Premier League is the best league in the world, in my opinion," he said.

"Liverpool have a great team and I think it's the place for me to be at the moment.

"I know there have been some great teams here in the past and the club has won a lot of trophies and I want to be a part of it."

Rodgers, speaking after the United match, said reinforcements were necessary if Liverpool were to continue their excellent start to the season.

"We need that depth and more numbers. If we can get them over the line, they are quality players.

"And having competition for places is a nice problem to have."

Liverpool's victory over United left them two points in front of Chelsea at the top of the Premier League and meant they were the only team in the division with a perfect played three, won three record so far this season.