The International Accounting Standards Board said that the Financial Accounting Standards Board’s recently issued guidance on fair value measurement is consistent with its existing guidance, but it still sees a need to revise its own controversial standards to account for the impairment of illiquid assets.

The IASB has set out a detailed six-month timetable for publishing a proposal to replace its existing standard for financial instruments, IAS 39, “Financial Instruments: Recognition and Measurement.” European Union Internal Market Commissioner Charlie McGreevey and other EU finance ministers have been pushing for more immediate changes in the impairment standards to match the U.S. revisions recently announced by FASB, but the IASB has rebuffed them for now, according to Reuters.

The IASB has been criticized for bowing to pressure from the EU and French President Nicolas Sarkozy to quickly amend IAS 39 last year, and IASB Chairman Sir David Tweedie (pictured) said he came close to resigning because of the political interference he experienced (see Pressured IASB Chairman Considered Resigning).

FASB Chairman Robert Herz has also come under criticism for bowing to pressure from Congress and banking interests in revising the fair value and mark-to-market standards on an accelerated schedule of three weeks, allowing banks to show better results for the first quarter (see Goldman, Citi Accused of Accounting Tricks). Although the IASB is taking more time to revise IAS 39, it apparently considers itself to be more or less in sync with the U.S. on fair value accounting.

The IASB said that the guidance on fair value measurement issued by FASB is consistent with the existing guidance on IFRS contained in a recent report by the IASB’s Expert Advisory Panel, “Measuring and Disclosing the Fair Value of Financial Instruments in Markets that are No Longer Active.” Therefore, the IASB claimed, “a level playing field exists in this area.”

To ensure ongoing consistency in the application of IFRS and U.S. generally accepted accounting principles, the IASB plans to include the relevant guidance in an exposure draft on fair value measurement that it intends to publish in May. But the IASB has signaled that it won’t be rushed this time into revising an important standard in a weekend’s time to please some politicians and bankers.

“We have heard a clear and consistent message on financial instruments accounting—fix this once, fix it comprehensively, and fix it in an urgent and responsible manner,” said Tweedie in a statement. “The IASB is committed to do just that by developing proposals within six months for public comment.”