Picture This: The dollar at 100 Yen

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Japan's new government has vowed to revive the economy and expectations for aggressive monetary easing are running high. This sets the scene for the yen, which has fallen sharply and quickly in recent weeks, to weaken to the 100-mark versus the dollar, possibly this year, some analysts say.

The yen, trading at about 87 per dollar, has shed about 11 percent since mid-November when Shinzo Abe, who became Japan's new prime minister following elections last month, promised a more aggressive monetary policy.

Keen to tackle the deflation that has dogged Japan's economy for years, Abe wants the cautious Bank of Japan to adopt a 2 percent inflation target – something the central bank is expected to consider when it meets later this month.

(Read More: Is the Bank of Japan Already Dancing to Abe's Tune?)

"Japan will be interesting to watch this year and it strikes me that they (policymakers) are finally serious about fighting deflation and stimulating growth," Richard Jerram, chief economist at Bank of Singapore told CNBC Asia's"Squawk Box" on Tuesday.

"The yen has fallen quickly and once it gets going, it gets going. What we're saying is what kind of number (in dollar/yen) do you need to fight deflation? I think we need to see dollar/yen at 110, 20 to say you're on top of the deflation problem," Jerram added.

Inflation in Japan fell 0.2 percent in November from a year earlier, after a 0.4 percent decline in October. A weak currency, brought about by aggressive monetary easing would help boost inflation, analysts say.

Japan's new government on Tuesday published a draft of an economic stimulus package, saying it wants to create a framework in which it can work closely with the Bank of Japan (BOJ) to bring an early end to deflation.

Three Month Chart of Dollar/Yen

Currency analysts at Societe Generale expect the yen to weaken a further 10 percent this year to 97 per dollar, adding that the conditions for the yen to weaken to 100 are in place.

"As the 'less strong yen' policy becomes credible, Japan will see capital flight which, allied to a rapidly vanishing current account surplus, is a recipe for overshoot," they said in a research note last week, referring to Japan's current account surplus, which fell 29.4 percent in October from a year earlier to 376.9 billion yen ($4.58 billion) on a fall in exports.

They say another reason to expect further yen weakness this year is a brighter outlook for the global economy, which means there is more incentive for Japanese investors to put their money overseas.

"Everything is in place for a move in dollar/yen to 100, the only constraint being resistance from other major central banks to anyone else adopting a weak currency," Societe Generale said.

Analysts say the problem with an aggressive monetary easing policy to weaken the yen is that it is likely to meet with resistance from other major central banks. A weaker yen after all, would be at the expense of an export-crimping rise in the value of other major currencies such as the U.S. dollar or euro.

"Japan has almost struck the first blow here by saying, if our currency goes down that's our right to drive that outcome," Bank of Singapore's Jerram told CNBC, highlighting currency wars as a potential tail risk for financial markets in 2013.

(Read More: Just How Low Will the Yen Go?)

Hold On, Not So Fast

Ray Attrill, global head of currency strategy at National Australia Bank, says that while he agrees with the underlying rational for a move higher in the dollar to 100 yen, further yen weakness at this stage may be overdone.

"While we will see some monetary easing from Japan coming through in the first quarter, the risk is that it might fall short of what the market is primed," he said.

Attrill adds that because monetary easing by the U.S. Federal Reserve this year via its asset purchase program is likely to be greater than monetary easing by the BOJ, pressure on the dollar to weaken will limit any further move higher in the dollar/yen exchange rate.

"So, even if the BOJ becomes more aggressive over the course of the year, it's probably going to be less aggressive than the Fed is going to be and that's a factor that makes us a little more cautious about calling dollar/yen up at say 100," Attrill said.

(Read More: Betting on Yen to Fall Further in 2013? Think Again)