The event will be backed by the Confederation of Indian Industry (CII) and India's commerce ministry.

Bilateral trade between the two countries was around 5 billion US dollars a year up 65 percent with more Sri Lankans importing Indian goods.

India is also the largest source of tourists to Sri Lanka. Sri Lanka's state airline is one of the foreign carriers flying most often to India.

Sri Lankan and Indian citizens have traded with each other from ancient times.

But trade freedoms were systematically stolen from them especially in the second half of the last century, after native rulers gained control of a European-style state structure backed by police, customs authorities and a legislating national assembly.

In South Asia, economic nationalism and trade barriers were partly triggered by global currency weakness of the post World War II failed Bretton Woods unstable peg system, though global trade barriers also rose during the Great Depression.

Until the middle of the last century exchange rates between the two countries were fixed one-for-one through a currency board in Sri Lanka.

Even after the creation of the Reserve Bank of India in the 1930s the Indian rupee remained strong and stable as the RBI was restrained by a gold standard.

But after independence from British rule, the central banks of the two countries raced with each other to weaken their currencies by printing money to finance budget deficits, a battle which was eventually won by Sri Lanka.

By 1950 both rupees were 13.33 units to the Sterling pound and 4.76 to the US dollar soon after the British pound was devalued 30 percent in 1949.

Rather than stop printing money (tightening monetary and fiscal policies), many countries at the time imposed trade and exchange controls as the Bretton Woods peg system started to collapse amid rampant worldwide inflation perhaps for the first time in human history.

In 1966 India devalued for the first time with Indian rupee falling from one rupee to 75 Sri Lanka cents. Britain devalued again. Sri Lanka followed a year later.

Gulf countries, like Bahrain, Qatar and Oman abandoned the Indian rupee which had the status of the US dollar in the area and produced their own stronger currencies.

As the Bretton Woods collapsed in the early 1970s amidst a commodity bubble as the US printed money for the Vietnam War, creating floating exchange rates Sri Lanka completely closed the economy in favour of import substitution, generating 20 percent plus unemployment.

Beggars died in streets after foraging in trash heaps.

Sri Lanka's rupee however weakened below that of India from 1977, when Sri Lanka lifted trade barriers but ran unprecedented budget deficits which were monetized by the Central Bank.

By 1978 Sri Lanka's rupee had fallen to 29.97 to the US dollar and an Indian rupee was worth 1.91 Sri Lanka rupees.

In 1991, following a severe balance of payments crisis in India more economic freedoms were given to citizens and the Reserve Bank of India stepped back from monetizing debt leading to stability in the rupee.

Both the Central Bank of Sri Lanka and Reserve Bank of India are now having currency trouble again amid sterilized foreign currency sales to defend the exchange rate.

The Sri Lanka rupee is now 130 units to the US dollar and the Indian unit about is about 55.