Liverpool have suffered a blow after England defender Trent Alexander-Arnold was ruled out for several weeks with a knee injury suffered in last weekend's FA Cup win at Arsenal.

Reds assistant manager Pep Lijnders confirmed Alexander-Arnold's injury when he spoke to the media on Tuesday ahead of Wednesday's League Cup semi-final first leg against Fulham.

Alexander-Arnold was able to finish Sunday's 2-0 third round victory over the Gunners, but the knee tear means he will spend an extended period on the sidelines.

The influential England right-back's absence is a significant setback for Premier League leaders Liverpool, who are also chasing silverware in the Europa League as well as the two domestic cups.

"First of all, some not-that-good news, Trent hyper-extended his knee during the last game," Lijnders said.

"So he has a little tear in the lateral ligament of his knee and he will need time to recover. He had a scan and he will be out for a few weeks, so let's see after that.

"He will get some rest and then hopefully he can come back to where he was."

After Wednesday's League Cup tie, Alexander-Arnold will miss a Premier League clash with Bournemouth on January 21, then the second leg at Fulham three days later.

Liverpool will play Norwich or Bristol Rovers in the FA Cup fourth round on the weekend of January 27 before taking on Chelsea in the Premier League on January 31.

"It is a big blow as he was one of our most important players. Even in bad spells he was the one putting the balls where we needed the difference," Lijnders said.

"Because this guy was decisive in all the games and was the one who created constantly for us from deep and gave the team a high level of flexibility.

"We will really miss him. We will have to find new dynamics without him because he made our game flexible but hopefully it is three weeks."

It wasn't all bad news for Liverpool on Tuesday as Lijnders said Netherlands centre-back Virgil van Dijk was available to face Fulham after missing the Arsenal game due to illness.