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                                                                    Exhibit 99.1

PERSONAL AND CONFIDENTIAL


September 21, 2000


Board of Directors
Paine Webber Group Inc.
1285 Avenue of the Americas
New York, NY 10019

Re: Registration Statement on Form F-4 of UBS AG filed on September 21, 2000


Lady and Gentlemen:

Reference is made to our opinion letter dated July 12, 2000 as to the fairness
from a financial point of view to the holders (other than UBS AG ("Buyer") or
any of its subsidiaries) of the outstanding shares of Common Stock, par value
$1.00 per share (the "Shares") of Paine Webber Group Inc. (the "Company") of
the Consideration (as defined in the opinion letter) to be received for Shares,
in the aggregate, pursuant to the Agreement and Plan of Merger, dated as of
July 12, 2000, among Buyer, Neptune Merger Subsidiary, Inc., a wholly-owned
subsidiary of Buyer, and the Company.

The foregoing opinion letter was provided for the information and assistance of
the Board of Directors of the Company in connection with the transaction
contemplated therein and is not to be used, circulated, quoted or otherwise
referred to for any other purpose, or is it to be filed with, included in or
referred to in whole or in part in any registration statement, proxy statement
or any other document, except in accordance with our prior written consent. We
understand that Buyer has determined to include our opinion in the
above-referenced Registration Statement.

In that regard, we hereby consent to the reference to the opinion of our Firm
under the captions "Summary -- Opinion of Paine Webber's Financial Advisors,"
and "The Merger -- Opinion of Paine Webber's Financial Advisors" and to the
inclusion of the foregoing opinion in the Proxy Statement/Prospectus included
in the above-mentioned Registration Statement.
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Paine Webber Group Inc.
September 21, 2000
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In giving such consent, we do not thereby admit that we come within the
category of persons whose consent is required under Section 7 of the Securities
Act of 1933 or the rules and regulations of the Securities and Exchange
Commission thereunder.

Very truly yours,


/s/ GOLDMAN, SACHS & CO.
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(GOLDMAN, SACHS & CO.)