* Index provider reviewing new disclosures, will update

in June

* MSCI ( MSCI ) in January warned Indonesia risks downgrade over

transparency problems

* Indonesia is worst-performing major stock market in

Asia

(Adds details from MSCI ( MSCI ) announcement, and comments from

Indonesia stock exchange acting CEO and investor)

By Mrinmay Dey and Ankur Banerjee

April 21 (Reuters) - MSCI ( MSCI ) said on Monday it

will extend its review of Indonesia's stock market by a month to

June to assess reforms announced by the Southeast Asian nation,

after a warning in January triggered a market rout and a foreign

investor exodus.

The global index provider had warned that Indonesia could be

downgraded to "frontier" market status from "emerging" as a

result of transparency problems.

That has led to Jakarta's stocks tumbling 12% this

year, making it the worst-performing major stock market in Asia,

and foreigners selling roughly $2.3 billion worth of stocks on a

net basis.

MSCI ( MSCI ) said it was reviewing the new data sources and

regulatory measures announced by Indonesia's financial

authorities, adding it would provide further updates in a June

review.

But for now MSCI ( MSCI ) said it would continue to freeze increases

to foreign inclusion factors and the number of shares for

Indonesian securities. It will also refrain from adding

Indonesian stocks to its investable market indexes or allowing

any upward migration across size segments.

Mohit Mirpuri, a fund manager at SGMC Capital, said MSCI's ( MSCI )

latest statement was largely in line with expectations.

"This reinforces MSCI's ( MSCI ) measured, wait-and-see approach,

engaging constructively with the reforms, but needing more time

to assess implementation," said Mirpuri. "For now, the market

remains in a holding pattern, with June as the next key

catalyst."

Jakarta stocks fell 0.8% in early trading.

Indonesia stock exchange acting CEO Jeffrey Hendrik said on

Tuesday the exchange met with MSCI ( MSCI ) last week and will continue

communication with the index provider.

"We will also continue to engage with global investors to

gather input on strengthening the capital market in the future,"

Hendrik said in a statement.

INDONESIA'S REFORMS

Since MSCI's ( MSCI ) warning in January, Indonesia has unveiled key

stock market reforms, including the release of more detailed

shareholder data and the doubling of the minimum "free float" of

tradeable shares for listed companies to 15%, a move aimed at

increasing liquidity and preventing stock price manipulation.

The MSCI ( MSCI ) announcement comes a week after rival index

provider FTSE Russell kept Indonesia's classification as a

secondary emerging market unchanged and said it was not

considering the country for inclusion on its watch list.

MSCI ( MSCI ) said it would not incorporate the new disclosures or

data sources into its free-float assessments or index

calculations until its review is completed and feedback from

market participants has been assessed.

"This approach is designed to limit index turnover and

investability risks while allowing time for further evaluation

of the recently announced reforms," MSCI ( MSCI ) said.

The index provider said it would continue engaging with

market participants and Indonesian authorities.

(Reporting by Mrinmay Dey and Chris Thomas in Mexico City,

Ankur Banerjee in Singapore; Editing by Daniel Wallis and

Muralikumar Anantharaman)