Further monetary easing, via an increase in asset purchases, also cannot be ruled out with financial markets vulnerable to any sudden worsening of developments in Europe's debt crisis.
Data released on Monday showed Japan's economy shrank more than expected in October-December, underscoring the pain from slowing global growth and a strong yen.
But with Sunday's approval of a key austerity bill by Greek lawmakers and the yen pulling back from record highs, the BOJ may find it hard to justify loosening policy now and instead debate setting a clearer price goal in response to growing political calls for one.
"The BOJ is likely to stand pat on monetary policy for the time being barring a sudden rise in the yen, as it has already taken into account the economy's underlying weakness," Yoshiki Shinke, senior economist at Dai-ichi Life Research Institute, said after the data.
The central bank may tweak its wording to clarify that it will aim to achieve consumer inflation of 1 percent, or signal that a major revision to its price commitment is under way, analysts say.
"At this meeting, the BOJ may clarify its phrase defining the median (desirable consumer inflation) at 1 percent so that it becomes close to a price goal," said Takahide Kiuchi, chief economist at Nomura Securities in Tokyo.
While that would hardly be enough to please politicians demanding bolder action, it is probably the least it can do for now to prevent them from following through on their threat to revise the BOJ law to give the government more room to intervene in monetary policy, analysts say.
BOJ Governor Masaaki Shirakawa was grilled in parliament last week by lawmakers who may face a snap election, and the government is worried that growth may not be robust enough to stomach tax increases proposed to fix stretched public finances.
Economics Minister Motohisa Furukawa weighed in, saying on Sunday he hopes the central bank examines a way to make its price commitment easier to understand. He repeated his calls for more action on Monday, a rare move by a cabinet minister on the day the bank's board was meeting.
"It's clear that the government and the BOJ need to work even harder than before to put a stop to deflation, and I expect the BOJ to take firm monetary policy measures when needed," he told a news conference.
MORE EASING?
The BOJ pledges to keep ultra-low interest rates until an end to deflation is in sight, and defines desirable long-term price growth as consumer inflation of 2 percent or lower with the median for the nine-member board at 1 percent.
It has described this as the board's "understanding" of desirable inflation rather than an explicit price target, for fear of binding its hands on policy.
But this has drawn criticism from lawmakers as too vague compared with the Fed's 2 percent inflation target and its extended commitment to near-zero rates announced last month.
The BOJ is due to review the loose price goal in April as a regular practice. It may move forward this schedule in the face of political pressure. But the consensus-favoring board may lack time to agree on Tuesday to any substantial changes such as setting a higher price target or a deadline to achieve it.
That means it may try to appease lawmakers by modifying its language, which could disappoint markets and further heighten political calls for bolder action.
Growing political pressure amid signs of economic weakness means that even if the BOJ refrains from action on Tuesday, it may loosen policy in March.
The BOJ has expressed its readiness to act if Europe's debt crisis, slowing overseas growth and a strong yen threatened Japan's fragile economic recovery.
But with rates virtually at zero, central bankers also want to save ammunition in case Europe's crisis flares up again, spilling over to global credit and financial markets.
If the BOJ were to ease policy, the most likely step would be to further top up its 55 trillion yen ($708 billion)asset buying and lending scheme, under which it buys government and private debt and lends cheap funds against various types of collateral.
(Additional reporting by Stanley White; Editing by Tomasz Janowski and Joseph Radford)
