THE Securities Investors Association Singapore (SIAS) has appealed to the Singapore Airlines (SIA) board for a revision of the group's takeover offer for Tiger Airways.

This comes a week after independent financial advisor (IFA) Maybank Kim Eng delivered a "fair and reasonable" opinion on the 41 Singapore cents per share offer.

In a letter to the SIA board on Friday, SIAS chief David Gerald singled out the concerns of long-term Tiger minority shareholders, saying: "These are the shareholders who are not satisfied and may not accept the offer. The reason for their investing in Tiger Airways, they say, is because of the fact that SIA was behind Tiger. This fact brought them comfort."

SIA - which holds a near 56 per cent stake in Tiger - announced in November that it was seeking to delist and privatise the low cost carrier to fully integrate it within the SIA group. SIA's offer price is a premium of around 32 per cent over Tiger's closing price on Nov 5. Tiger shareholders can also subscribe to SIA shares at S$11.1043 per share as a way of participating in Tiger's future growth.

In his letter, Mr Gerald pointed out that SIA "was prepared to pay more" when it acquired Temasek's 7 per cent stake in Tiger at S$0.678 in 2013, but appears unwilling to pay more to Tiger's minority shareholders to take it private. Tiger's minority shareholders have also highlighted to SIAS that SIA paid $S0.565 per share to beef up its stake in Tiger from 40 per cent to 55.8 per cent - a move made possible due to an earlier whitewash waiver granted by minority shareholders.

"It is also to be noted that the IFA report did not take into consideration these factors," Mr Gerald added, requesting a two-week extension to the Dec 28 deadline for the close of offer, given the upcoming holidays.