The Nikkei ended the day up but dropped back after some strong gains early in the session.
Today's (October 1st) trading saw the index rise initially but then fall on concerns over the US government shutdown, which has been enforced after Congress could not agree a budget deal.
At the end of the session, the benchmark Nikkei closed at 14,484.72 after a 0.2 per cent rise, but this was a slip from the 1.3 per cent gains it had racked up earlier in the day.
According to a report by Reuters, Japanese prime minister Shinzo Abe is now expected to announce a new stimulus package designed to boost the Asian nation's economy.
The Nikkei is up around 39 per cent for the year and has picked up a run of four weekly gains in a row, though it started the new week with a 2.1 per cent dip in its value yesterday.
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