IASB's Tweedie to retire when term ends in 2011

* Tweedie to retire after two terms in June 2011

* Trustees hope to name successor in mid-2010

* Tweedie has led push for global adoption of IFRS

NEW YORK, Dec 7 (Reuters) - Sir David Tweedie, Chairman of the International Accounting Standards Board (IASB), will retire when his term ends in June 2011, and the foundation that oversees the London-based accounting rule maker said on Monday it has begun searching for a successor.

Tweedie will retire at the end of June of 2011 when he completes his second term as the head of the IASB, which writes International Financial Reporting Standards (IFRS) for more than 100 countries.

The trustees of the International Accounting Standards Committee Foundation, which oversees the board said on Monday they have launched a global search for his successor and expect to make a decision in the second half of 2010.

Tweedie, a former partner at accounting firm KPMG [KPMG.UL], was appointed Chairman of the IASB in 2001. Prior to that he had been the first full-time chairman of the UK accounting standard setter, the Accounting Standards Board.

In his tenure at the IASB, Tweedie has led the push for more countries to switch from local accounting standards, to IFRS, greatly increasing the harmonization of accounting standards around the world. He is closely involved in an effort among accounting rule makers to converge U.S. accounting rules with IFRS.

Tweedie considered resigning from his post late last year, amid the financial crisis, after political leaders effectively forced his board to change rules on mark-to-market or “fair value” accounting.

But he has said he stayed because he wanted to continue the convergence process, which is beginning to reach its goal of having a single set of high quality accounting standards used around the globe. The U.S. Financial Accounting Standards Board and the IASB have redoubled efforts to complete their major convergence projects by a June 2011 deadline set by the G20 group of leading countries.

U.S. securities regulators are expected to say this month whether they will continue with a proposed road map that would have U.S. companies using IFRS as soon as 2014, instead of U.S. Generally Accepted Accounting principles. (Reporting by Emily Chasan; editing by Andre Grenon)