HONG KONG, Oct. 19 (Reuters) - Asian credit spreads widened slightly on Monday as a host of debt offerings emerged in the region, but new Philippine bonds were rescued off lows by onshore bids after they traded below the issue price in New York last week.

The Asia ex-Japan iTraxx investment-grade index was quoted at 101 basis points after falling below the 100 mark last Friday for the first time since May 2008.

Philippines, one of the most frequent bond issuers in Asia, sold 25-year bonds last Friday pricing them at the low end of the initially indicated yield range following orders in excess of $5 billion for the $1 billion offer.

But in initial trade in New York, the bonds fell half a point below the issue price of 99.382 cents on the dollar with US investors accounting for 37 percent of the allotments, the highest by region. Philippine and rest of Asia buyers took 25 percent each, with Europe taking up the rest.

''Most of the trading is in the new bond. The market is not reacting to the samurai bond supply, it's been in the news for some time now,'' said a Manila-based trader.

The new bonds traded as high as 101 before settling at 100.625 in Asian trade on Monday.

By investor type, banks took 55 percent, funds 34 percent and retail investors 11 percent of the issue.

The Philippines is still considering a sale of Samurai bonds this year as it seeks to secure most of its 2010 debt needs of about $2 billion ahead of the May presidential polls.

The broad market is waiting for the response to a host of new offerings which have been announced recently, many of them expected to open for subscription this week.

Singapore state investor Temasek Holdings , State Bank of India and Chinese chemical maker Lumena Resources are some of the borrowers who could complete transactions this week.

''It's a massive cash flow story,'' said a Hong Kong-based banker on a debt syndication desk. ''There is money coming off the sidelines, looking for returns. It is a constructive time for doing a transaction.'