Take That have pleaded with former bandmate Robbie Williams to join them on their new UK tour. The band - Gary Barlow, Mark Owen, Howard Donald and Jason Orange - have just announced plans for their 22-date 'Beautiful World Tour' and want troubled Robbie to join them. Howard said: "It would be lovely to have Robbie join us and let's just say we're keeping in touch about it."Having Robbie sing a few numbers would be amazing and we'll have to wait and see if he's up for it. We certainly are."Robbie - who is undergoing treatment for addictions to prescription drugs ina US rehab clinic - was mooted to appear with the band when they embarked on their reunion tour last year. However, the 'Rudebox' singer - who left the band in 1995 - only featured as a 20 foot pre-recorded hologram for hit 'Could It Be Magic'. Since reforming, Take That have had a successful tour, a number one album, 'Beautiful World', a number one single, 'Patience', and won the BRITS British Single award. Their 2007 arena tour begins in Birmingham on November 16. Tickets go onsale on Friday at 9am.