The Citywire + rated manager has sold down positions in Taiwan, Thailand and Indonesia on the expectation of further near term volatility in the region sparked by concerns over the onset of US tapering.
He told Citywire Global: 'Those EM countries with a balance of payment deficit who have been funding it with US debt look vulnerable. Indonesia is facing particularly strong headwinds as it is also a commodity-based economy.'
'I prefer those economies that have an account deficit and low labour costs.'
Thornber points out that one positive trend is a number of emerging market economies being able to boost corporate margins as they fill the gap left by China as its manufacturing base looks to move up the value chain.
'Company profitability has been held back in countries like the Philippines, Turkey, Thailand and Mexico, but they are all able to reclaim business from China as it moves up the valuation chain.'
Adding to US consumer stocks
In response to a gradual pick up in developed world growth, Thornber has added BNP Paribas as a best of breed bank with an attractive wealth management business.
He said: 'We wanted a lower risk lower beta play as we are still not confident enough to go into Spanish or Italian banks.'
Despite the recent increase in exposure to the US, Thornber remains underweight the country overall at about 35% of the fund, because the market has relatively few stocks that meet his 4% income yield requirement.
However, Thornber has added US theme park operator 6 Flags and retail chain Limited Brands to gain greater exposure to the US consumer.
'We still like the US but we have to be careful where we play it. We like high yielding stocks that can benefit from a pick up in the housing and autos markets and the spending power of the US consumer.'
Thornber expects the onset of tapering to spark further short term volatility for equities, but he is optimistic that the market will be able to look beyond this phase of the transition.
Gradual tapering process
'When it starts it will remain volatile but hopefully once people see that the world has not ended things will calm down,' he said.
'QE will still continue in Europe and Japan so we hope the market can gain confidence from a very gradual tapering process.'
Thornber admits that no markets are 'obviously cheap' any longer but he still hopes to see 8-10% earnings growth in 2014.
'Investors still want and need income and equities continue to look attractive relative to bonds.'