(Sharecast News) - Wall Street futures were in the green as before the bell as Federal Reserve chairman Jerome Powell heads to Washington DC to testify before Congress.

As of 1240 BST, Dow Jones futures were up 0.05%, while S&P 500 and Nasdaq-100 futures had the indices opening 0.21% and 0.35% higher, respectively.

The Dow closed 31.08 points lower on Monday, while the S&P 500 and Nasdaq Composite closed at fresh record highs.

On Tuesday's macro slate, the National Federation of Independent Business' business optimism index rose to 91.5 in June, up from 90.5 a month earlier, for the highest reading since the start of 2024. The reading came in ahead of expectations for a slowdown to 89.5 but remained well and truly belpw the long-term average of 98.

NFIB chief economist Bill Dunkelberg said: "Main Street remains pessimistic about the economy for the balance of the year. "Increasing compensation costs has led to higher prices all around. Meanwhile, no relief from inflation is in sight for small business owners as they prepare for the uncertain months ahead."

Still to come, Federal Reserve chairman Jerome Powell will testify before Congress at 1500 BST, while Federal Reserve vice chair Michael Barr and governor Michelle Bowman will deliver speeches at 1415 BST and 1830 BST, respectively.

In the corporate space, BP shares were sharply lower after the energy giant warned investors that it would be faced with an impairment charge of between $1.0bn and $2.0bn. It also warned of lower refining margins in Q2.

Reporting by Iain Gilbert at Sharecast.com