"We have had positive and constructive talks that have led to an agreement," Brown told Reuters in an interview, but would not be drawn on what the wording in the group's communiqu‚ would actually be. Finance ministers and central bankers are meeting on Saturday and are expected to issue a statement late this afternoon.
He said Britain's position had always been that exchange rates should reflect economic fundamentals.
He praised the Bank of England, which on Thursday raised the country's interest rates, for its "pre-emptive, forward-looking approach" to monetary policy.
But he would not be drawn out on whether he thought the European Central Bank should cut euro zone interest rates to ease the burden of the bloc's appreciating currency.
"That is a matter for the ECB," he said, adding that euro-zone countries should accelerate economic reforms to make their economies more flexible and to reduce unemployment.
European sources close the talks said the Group of Seven finance ministers agreed to language that calls for a stabilisation of the dollar, which has been in a precipitous slump, especially against the euro, since the last G7 meeting in September in Dubai.
One source told AFP that a final statement issued at the Boca Raton, Florida, meeting would make explicit mention of a G7 appeal for "the avoidance of excessive volatility" on foreign exchange markets.
However, the statement was also expected to keep the mention of "flexibility," seen as a message to Asian nations to avoid massive intervention to keep their currencies artifically low.
The source said the G7 would "clarify" language used in the last G7 statement.
Another source involved in the talks said the statement retains the use of the term "flexibility," but declined to describe the full text.
Finance ministers and central bank heads from Britain, Canada, France, Germany, Italy, Japan and the United States had been in a contentious debate over the language of the final statement, due later Saturday.
While eurozone authorities had been seeking language in the Boca Raton final statement aimed at restoring the dollar's luster, they had encountered resistance from the United States, for which a weaker dollar spurs exports and economic growth.
European and Japanese authorities maintain that a recent pickup in global momentum could be jeopardised by imbalances in the world economy. They point in particular to huge budget and current account deficits in the United States that weaken the dollar, as investors shun the greenback, and hamper growth efforts elsewhere.
Japanese Finance Minister Sadakazu Tanigaki said he told US Treasury Secretary John Snow earlier at the Boca Raton meeting that Tokyo remains prepared to intervene in currency markets to support Japan's export-led recovery.
"I insisted (that) if we see speculative moves, each country should be determined to do what is necessary to regain stability," the Japanese official said.
Eurozone officials had suggested that the Bush administration, by steadfastly refusing to stem the dollar's slide, is in effect trying to export its way back to economic health.
Snow said earlier he saw the issue as one of growth rather than market intervention.
"The focus of the conference, from my point of view, will continue to be growth and what we as ministers can do to build support for a higher growth in our domestic economy of our country and the economies of the world," he said.
"We have had a growth gap, a growth deficit, for some time," he added.
European authorities have recently managed to "talk down" the euro a bit. The single European currency has been hovering around 1.25 dollars after hitting a high of 1.2898 in early January. As the talks got underway Friday, the euro surged past 1.27 dollars.
While they may have been at odds on some key issues, Europe and the United States agreed that Asian currencies, notably the yen and the yuan, should be allowed to appreciate freely, unfettered by central bank intervention.
China has so far resisted Bush administration pressure to abandon its dollar-yuan peg, which Washington says unfairly undervalues the Chinese currency.