NEW YORK: The dollar on Tuesday fell from last week's two-month highs, weighed down by currency flows in the options market as well as for month end, with investors also capitalizing on recent gains in the greenback ahead of the first debate between two US presidential candidates.

"Today the market is mostly flows-driven, options-related and month-end flows that have pulled the dollar lower," said Erik Bregar, head of FX strategy at Exchange Bank of Canada in Toronto.

There were FX options-related flows that bet on the downside in the dollar versus the yen as well as the upside on the euro against the Japanese currency, Bregar said. The euro/yen options have pulled euro/dollar higher.

The 90-minute televised debate at 9 p.m. EDT (0100 GMT) will be watched by investors looking for guidance on the candidates' prospects. In mid-morning trading, the dollar index fell 0.3% to 93.901, after hitting a two-month peak on Friday.

The euro firmed across the board, rising 0.5% against the dollar to $1.1727 and 0.6% versus the yen to 123.84 yen. The dollar fell to a one-week low against the Swiss franc and was last down 0.5% at 0.92 franc. The pound was last up 0.4% at $1.2883.