* C.bank seen shifting rouble's floating band to 34.75
* Tax bills, strong crude prices to support rouble this week
* But rally seen reaching "ceiling"
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By Lidia Kelly
MOSCOW, Feb 24 (Reuters) - The Russian rouble extended its gains on Wednesday, disregarding the latest rate cut and forcing the central bank to intervene, but analysts said the rally may run out of steam once month-end tax payments are over.
In a fifth such move since last week, the central bank moved the floating rouble band boundary to 34.75 versus the dollar-euro basket from 34.80
The central bank shifts the boundaries of the floating rouble corridor by 5 kopecks for each $700 million in purchases, making the rouble's rise less rapid.
At 1240 GMT the rouble traded at 34.82 versus the basket, after strengthening earlier in the session as far as 34.78 -- its strongest since December 2009.
Monthly tax payments, which come due this week -- estimated to possibly demand as much as 500 billion roubles ($16.66 billion) -- along with oil prices hovering around $78-$79 a barrel [O/R], have been pushing the rouble higher.
"The pressure on the central bank bid level is likely to persist this week," Nikolai Podguzov, the head of fixed income strategy at Renaissance Capital, said in a note.
The rouble's firming came despite the central bank engineering yet another gradual rate cut, effective as of Wednesday, which brings the benchmark refinancing rate to a record low at 8.50 percent. [ID:nLDE61I0H8]
RALLY TO EASE
The rouble's recent wave of appreciation has been most pronounced against the globally weakening euro, against which it rose to its strongest since late 2008 last week
Versus the dollar, the rouble has held broadly stable, trading at 30.02 per dollar
For many investors and ordinary Russians alike the rouble's position versus the dollar remains the most telling indicator of the currency's might.
In the medium term, investors see the rouble changing very little against the dollar, with 1-year non-deliverable forward (NDF) contracts -- a barometer of investors' sentiment towards the currency -- showing the rouble at 31.10
UniCredit reckons the rouble is also already "knocking on the ceiling," attributing the current rally partly to the tax payment demands and seasonal improvement in the budget balance.
The budget showed a weak surplus in January, but is expected to swing back to deficit this month as state spending increases.
"The rally has been driven by forces which are short-term in nature and so should start to ease and then reverse within a few weeks or even days," Vladimir Osakovsky, UniCredit's economist wrote in a note. (Reporting and writing by Lidia Kelly; Editing by Toby Chopra)