Image caption Samsung released its latest flagship product the Galaxy S4 last month

Shares in Samsung Electronics, the world's biggest smartphone maker, fell the most in nine months after JPMorgan Chase cut its profit estimates.

Samsung shares fell as much as 5.5% in early trade in Seoul to a four-month low of 1,438,000 South Korean won.

JPMorgan said weak demand for Samsung's flagship phone, the Galaxy S4, from Europe was likely to impact earnings.

It said it now expects S4 shipments this year to be 20 to 30% lower than its previous forecast.

It said the firm was expected to ship 7 to 8 million units per month from July. Last month, Samsung announced that it had sold 10 million S4 units within a month of the phone's launch.

JPMorgan analysts were quoted as saying by Bloomberg news agency that the S4's "peak-quarter number seems way below our previous estimates".

JPMorgan lowered its 2013 earnings forecast for Samsung by 9%.

'Lagging sales'

Profit warnings from analysts of other South Korea-based firms this week also dented investor morale.

"It's a general consensus that the profitability of Samsung's mobile business will weaken," Young Park from Woori Securities said in a note to clients.

Samsung has been shifting its focus to cheaper smartphones as it compete with Chinese manufacturers.

However, analysts said that such moves would put pressure on profit margins and slow growth momentum for its high-end models including the Galaxy S4.

"Sales of high-end handsets are lagging behind expectations, while low-to mid-end handsets are selling briskly worldwide," said Kim Young-chan from Shinhan Investment Corp.