Dow in record territory after market open

The Dow Jones industrial average and S&P 500 took baby steps further into record territory after Monday's market open, with the Dow staying in the green while the broader index hovered between positive and negative.

At 9:58 a.m. ET the Dow is up 0.1%, while the S&P 500 is down about 0.1%. The Nasdaq composite is off 0.4%.

On Friday, the Dow rose 0.1% to its all-time closing high of 16,717.17. The S&P 500 index rose 0.2% to its record close of 1,923.57. The only index to fall was the Nasdaq composite, which ended down 0.1% to 4,242.62.

Japan's benchmark index closed sharply higher on Monday. The Nikkei 225 index rose 2.07% to 14,935.92.

Sentiment was underpinned by the new closing highs for the Dow and S&P 500, as well as a weakening yen.

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Elsewhere in the region, trading was relatively subdued with markets closed for holidays in mainland China, Hong Kong, Taiwan and New Zealand.

May was the best month for U.S. investors since February. The S&P rose 2.1% for the month, while the Dow rose 0.8% and the Nasdaq rose 3.1%.

Major indexes in Europe are mixed so far.

Contributing: Kim Hjelmgaard, Associated Press