The construction of enormous skyscrapers has an "unhealthy" link with looming financial crises and investors should therefore keep a close eye on China and India, Barclays Capital said on Wednesday.

China is currently the biggest builder of skyscrapers, while booming India is constructing the second largest tower in the world, the investment bank said in its latest annual 'Skyscraper Index' survey.

"Our Skyscraper Index continues to show an unhealthy correlation between construction of the next world's tallest building and an impending financial crisis -- New York 1930; Chicago 1974; Kuala Lumpur 1997 and Dubai 2010," Barclays Capital said in a report.

"Yet often the world's tallest buildings are simply the edifice of a broader skyscraper building boom, reflecting a widespread misallocation of capital and an impending economic correction.

"Investors should therefore pay particular attention to China, today's biggest builder... and India, which with just two completed skyscrapers, now has 14 skyscrapers under construction."

Barclays Capital warned of a "bubble" in China, whose property boom has been powered by cheap liquidity.

"Looking forward, using skyscrapers under construction, it is evident that the skyscraper boom in China continues to grow," it said.

"China will complete 53 percent of the 124 skyscrapers under construction over the next six years, expanding the number in Chinese cities by a staggering 87 percent.

"China's skyscrapers are not only increasing in number -- it now has 75 completed skyscrapers above 240 metres in height -- but the average height of the skyscrapers that it is building is also increasing as past liquidity fuels the construction boom."

Barclays Capital meanwhile added that India was set to experience its largest boom in skyscraper construction.

"China is not alone in the growth of its building bubble ... India it seems is playing catchup," said Barclays Capital, the investment arm of major British bank Barclays.

"Today India has only two of the world's 276 skyscrapers over 240 metres (788 feet) in height, yet over the next five years it intends to complete 14 new skyscrapers, in what will prove to be its largest skyscraper building boom.

"Worryingly as well, India is also constructing the second tallest building in the world, the Tower of India, which should complete by 2016.

"The writing, so to speak, would seem to be already on the glass curtain walling.

"For if history proves to be right, this building boom in China and India could simply be a reflection of a misallocation of capital, which may result in an economic correction for two of Asia's largest economies in the next five years," Barclays Capital concluded in its report.

In London meanwhile, work on The Shard -- a 310-metre skyscraper that will become the highest tower in western Europe -- is set for completion this year.