JERUSALEM, Oct 6 (Reuters) - The Bank of Israel is expected to leave short-term interest rates unchanged this week for its 12th straight policy meeting, although the central bank may start preparing the markets for an eventual end to its very accommodative policy amid rapidly expanding growth and quickening inflation.

All 15 economists polled by Reuters believe the monetary policy committee (MPC) will keep the benchmark rate (ILINR=ECI) at an all-time low of 0.1% when the decision is announced on Thursday at 4 p.m. (1300 GMT).

While a rate increase is still viewed as at least a year away, analysts project the central bank will offer a less dovish outlook on policy given a fast rebounding economy and inflation at an eight-year high.

Following the near full opening of the economy in March that has led to a decline in unemployment, the economy grew an annual 16.6% in the second quarter over the prior three months.

On the heels of an aggressive campaign for a third COVID-19 vaccine shot, some 40% of the population has so far received the booster and strong growth is forecast in the third quarter as well.

The Bank of Israel's own economists foresee 5.5% economic growth in 2021 and 6% in 2022 but economists expect an upward revision to this year's estimate. Along with the rates decision, the central bank will issue its updated macro forecasts.

The new estimates will likely reflect a possible rate hike by the end of 2022, according to Leader Capital Markets Chief Economist Jonathan Katz.

Bank Hapoalim economist Victor Bahar believes the MPC may also change the phrasing in its forward guidance that a "rate cut and QE measures are not needed any more."

Analysts are split over the timing of the start of monetary tightening between late 2022 and in 2023. Much depends on inflation, which moved to an annual rate of 2.2% in August, its highest level since July 2013 and after turning positive in April.

However, "Although inflation has been rising recently, this is due more to base effects than rising price pressures, thanks to continued shekel strength," said Barclays economist Raisa Muhtar.

Based on bond yields, the inflation rate is expected to remain steady at 2.2% in a year's time. Israel has an official inflation target of 1-3% a year.

Another decision by the MPC led by Governor Amir Yaron is regarding central bank government bond purchases. Some economists expect the MPC to announce the programme -- which began in March 2020 -- will come to an end when purchases hit the top target of 85 billion shekels ($26 billion).

So far, the Bank of Israel has bought 75 billion shekels and has been buying at a pace of some 3 billion shekels a month.

Some, though, believe a decision could be delayed and the pace could slow into 2022 since a complete cessation might lead to further shekel appreciation due to narrower interest rate gap.

($1 = 3.2457 shekels)