S.Korea Sept manufacturing PMI lowest in 43 mths

SEOUL, Oct 2 (Reuters) - South Korea's manufacturing sector shrank in September for the fourth consecutive month and the most rapidly since early 2009, a survey showed on Tuesday, suggesting the export-reliant economy probably slowed further in the third quarter.

The HSBC/Markit purchasing managers' index (PMI) on South Korea's manufacturing sector fell to a seasonally adjusted 45.71 in September after having edged up to 47.50 in August from 47.20 in July, Markit Economics said in a statement.

It was the fourth month in a row that the index stood below 50 separating expansion from contraction in manufacturing activity, and the index hit the lowest since February 2009, when the global economy was in its worst slump in decades.

A sub-index on new export orders fell during the month of September to a seasonally adjusted 48.64 after having ticked up to 48.79 in August from 48.59 in July, also marking the fourth consecutive month of decline in export orders.

The bearish findings came after data showed on Monday the country's exports in September fell for the seventh month this year on an annual basis as Europe's debt crisis kept dragging on demand.

The weak set of indicators on the country's export-reliant manufacturing sector for September suggested Asia's fourth-largest economy lost further momentum in the third quarter and supported the market's expectations for an interest rate cut next week.

The central bank has already abandoned a July forecast that quarterly economic growth would rebound to above 1 percent in the July-September quarter from 0.3 percent in the second quarter.

The Bank of Korea cut the policy interest rate by 25 basis points to 3.0 percent in July in a surprise move, and has since kept it unchanged pending stimulus measures by the government.

(Reporting by Choonsik Yoo; Editing by Kim Coghill)

((choonsik.yoo@thomsonreuters.com)(+822 3704 5580)(Reuters Messaging: choonsik.yoo.thomsonreuters.com@reuters.net))