Citigroup has appointed Wei Christianson to be its new chairman for China investment banking. The appointment fills the two-month vacancy caused by the departure of previous incumbent Margaret Ren.

Christianson's appointment has been widely rumored for the past week or so, although it is understood she only finally signed her new contract yesterday.

Christianson is regarded as one of the best China bankers around. Working at Hong Kong's regulator in the early 1990s, she was one of the team responsible for drafting the rules allowing Chinese companies to list in Hong Kong.

She subsequently moved to Bank of America and then onto Morgan Stanley where she came into the orbit of John Mack. She moved with Mack across to Credit Suisse First Boston when he joined the firm in 2001 and held the title of chairwoman for China investment banking. When he was fired earlier this year, she left the firm as well.

An official statement explaining why Margaret Ren and her colleague Earl Yen left Citigroup earlier this year has never been released. The rumour mill in the region remains in full swing on probable reasons, although Citigroup will only allude to regulatory reasons for the dismissals.

CSFB has already filled the gap left by Christianson's departure with the hire last week of Zhang Liping. Zhang had been Merrill Lynch's main man in China in the 1990s until he left the rigours of investment banking for the joys of corporate life.

In the cut throat world of China investment banking, wags are already saying that CSFB is one up on Citi by releasing the news of his return to the noble profession before Citi could announce Christianson's move. Now the positions are both filled in time for the next expected wave of China deals later this year.

Christianson will be based in Beijing and report to Citigroup's global corporate and investment banking CEO for Asia Pacific, Robert Morse. "Wei has had a long and successful career in the China market," says Morse. "We believe she is an excellent addition to our strong China management team, which has sustained high growth momentum in recent years. We are very committed to expanding Citigroup's presence in China and we expect our strong investment banking business to be part of that expansion."