"It's a far clearer business decision for Standard Chartered as really a far purer emerging market bank with no banking network in the UK, no banking network in Europe," Hugh Young, managing director of Aberdeen Asia Management Asia, told Reuters in an interview on Tuesday.

A move to Singapore is logical for StanChart as its main franchise is in the city-state, besides Hong Kong and Africa, he said.

Aberdeen is the second biggest shareholder in Standard Chartered, with an aggregate 9.4 percent stake. Singapore state investor Temasek Holdings [TEM.UL] is the biggest shareholder in the British bank with a 17.7 percent stake.

HSBC and StanChart, who make most of their profits in Asia, face a combined $2 billion bill this year under the annual UK bank tax, up from $1.5 billion last year and almost double what they paid in 2013.

Several investors have said they want the two banks to do a thorough analysis on whether it makes sense to move after Britain raised the bank tax by a third last month.

A big jump in the tax on UK banks has made staying in Britain increasingly painful for both HSBC and StanChart.

"From a purely economic point of view, given it's taxed hundreds of millions for being in London and that's not really where its business is. Yes, in a sense it should move overnight," Young said, referring to StanChart.

He, however, noted the difficulties of such a move. "It's not easy to move the domicile of a bank and re-do everything."

On Monday, the chairman of HSBC, Europe's biggest bank, said that HSBC will look at whether to move its headquarters from London once the regulatory environment becomes clearer.

Aberdeen remains bullish on StanChart and is comfortable holding onto its stake. "I think it's fundamentally not a bad bank. Yes, it made some mistakes that banks make, but not fatal mistakes - relatively straight forward," Young said.

On the positive side, StanChart had a strong franchise in some long-term growth markets of the world at a very reasonable value, he said.

(Editing by Muralikumar Anantharaman)

By Anshuman Daga and Saeed Azhar