Speaking at a webconference alongside Azad Zangana, the group’s European economist, Brown said: "If Greece stays in [the monetary union] and is let off its debt it’s not going to do much to restore its competitiveness and structural imbalances.
"If Greece comes out then any exchange rate depreciation will leave it with sustained improvement in competitiveness."
Brown also downplayed the impact an end to the EMU would have on the macro-economics of the region.
He said if you took the loosest definition of a currency union, then 69 have come to an end between 1945 and 2005, a statistic he took from a research paper published by the Monetary Authority of Singapore (MAS).
In the paper the MAS said the fall out from previous monetary unions’ failure was fairly limited in its reach.
Certainly the domestic economy concerned, in this instance Greece, would feel the pain, but the overarching and systemic ramifications are not as bad as people might expect.
Brown said the 1992 exit of the pound from the exchange rate mechanism, while a slightly stretched example, showed that currency depreciation could help the economy over the longer term.
"It heralded in 15 years of low inflationary growth in the UK economy," he explained.
Zangana, however, was more measured in his assessment of the Greek situation: "Greece has been through currency crises in the past and they have within their memory the impact of what happens when you get 20-30% depreciation.
"Once you think about a default it is very difficult to actually control depreciation. It would lead to a very serious downturn in Greece, a 20-30% loss in real GDP terms in just the first year."
Meanwhile, other commentators continue to view the probability of a eurozone break up as very low.
Bill O’Neill, EMEA chief investment officer at Merril Lynch Wealth Manager, said: "This coming quarter will be dominated still by the euro crisis. We do not expect one or more countries to exit the euro and subsequently the European Union, either temporarily or permanently."
He pointed out the current legal system does not allow for a country to exit the single currency without leaving the entire EU and that it is legally impossible for a country to be expelled under current laws.
"The improvement in growth from currency depreciation might not offset the costs of exit. We place the probability of a breakup as very low, with the likely long term outcome being greater fiscal integration. However, this is unlikely to occur in the near term."
