Asian markets down on worry over U.S. debt show…

The threat that the partial shutdown of the American government could bring the world's largest economy close to defaulting on its debt was weighing on global markets Monday.

In Asia, Japan's Nikkei index, the regional heavyweight, slumped over 1% to 13,853.32. Hong Kong's Hang Seng index fell 0.7% to 22, 973.95 and India's BSE 30 index lost 0.5% to 19, 808.71. Mainland China markets were closed for a public holiday. Benchmarks across Europe were moving lower.

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Early-morning stocks were on the decline on Wall Street, too, ahead of Monday's opening bell. Dow Jones industrial average index futures fell 0.8%, Standard & Poor's 500 index futures slumped 1% and Nasdaq index futures were down 0.9%.

Wall Street stocks had posted modest gains Friday, driven by optimism at the time that Washington's bickering politicians would resolve their budget fight. The Dow rose 0.5%, to close at 15,072.58. The S&P 500 index added 0.7%, to 1,690.50. The Nasdaq rose 0.9%, to 3,807.75.

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But investor anxiety has risen as the U.S. budget impasse between Republicans and the White House drags on.

On Sunday, Republican House of Representatives Speaker John Boehner ruled out a vote on a straightforward bill to raise the government's borrowing authority without concessions from President Obama before an Oct. 17 deadline, moving closer to the possibility of default.

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"This has really rattled markets and is likely to result in further near-term weakness for global equities," Stan Shamu, a market strategist for IG investors, said in a note to clients.

SMG investment group also cited the U.S. political showdown as the reason for Monday's market declines, saying in an advisory that "the latest comments from politicians showed no signs of progress to r! esolve the budget standoff."

Benchmark oil for November delivery fell 61 cents to $103.23 per barrel in electronic trading on the New York Mercantile Exchange. The contract rose 53 cents to close at $103.84 on the Nymex on Friday.

Corporate earnings season will get underway this week.

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Contributing: Associated Press