U.S. stock benchmarks extended gains midday Monday, picking up steam after the U.S. and Mexico forged a bilateral accord on trade. Earlier, President Donald Trump issued a tweet that implied that a trade announcement was imminent. Trump tweeted. Details have been scant on the trade agreement thus far, but reports suggest that it would replace the North American Free Trade Agreement, with the current deal excluding Canada. However, Congress would be required to ratify any new trade pacts, according to reports. Wall Street participants speculate that the current U.S.-Mexico pact is partly intended to pressure Canada to reenter into Nafta talks that have been stalled. The Dow Jones Industrial Average DJIA, +1.33% rose 263 points, or 1%, to 26,052. The S&P 500 index SPX, +1.59% traded 23 points, or 0.8%, to reach 2,898, after closing at its first record since Jan. 26 on Friday. Meanwhile, the Nasdaq Composite Index COMP, +2.26% gained 78 points, or 1%, 8,023, hitting a psychological round-number level, and extending its move above a record, also hit on Friday. Both the S&P 500 and the Nasdaq put in fresh intraday all-time highs near the start of Monday trade.