Veteran Socceroo Tim Cahill has rejoined former club Millwall on a short-term deal, the English Championship side said, as the striker looks for more game time to secure his spot in the World Cup squad.

Cahill, who quit Melbourne City in December after rarely featuring in the starting line-up since joining the A-League side in 2016, played a key role in helping Australia qualify for Russia 2018.

"I'm really happy. I've had a great career as a footballer, but to come here now at this stage of my career, with eyes on a World Cup place, it's such a professional environment," Cahill told Millwall's website on Monday.

"The romance of the story is definitely not lost on me. I've always said that if I came back to England, I'd come home."

Cahill is Australia's most prolific international scorer with 50 goals and is seeking to represent his country for a fourth-consecutive World Cup in June-July.

The 38-year-old will join Millwall's squad for the rest of the 2017-18 season, which ends in early May ahead of the play-offs.

Millwall manager Neil Harris said the team would benefit from Cahill's wealth of experience and enthusiasm, adding that the Australian was "in terrific shape".

"When I played with him, I appreciated what he did. Since then, I've followed his career and admired what he has done and I know full well what he can bring to my dressing room," Harris said.

"To start with, we are thinking about impact -- someone to come off of the bench and give us that little lift, someone to lift the crowd and someone to pass on that knowledge when in front or behind."

Cahill debuted for Millwall in 1998 after leaving Australia to pursue a career in English football.

He made more than 250 appearances for the Lions before leaving in 2004 to join English Premier League side Everton. He later had stints with the New York Red Bulls, Shanghai Shenhua and Hangzhou Greentown.

Australian-born Cahill began playing for Western Samoa's under-20s and only became a Socceroo in 2004 after an intense lobbying campaign to world body FIFA.

He went on to become the first Australian to net a goal at the World Cup in Germany two years later, and has scored in three World Cups (2006, 2010, 2014) in total.

Cahill will be looking to impress new Socceroos coach, Dutchman Bert van Marwijk, who was appointed last week after the sudden departure of Ange Postecoglou in November.