AUGUSTA, Maine — U.S. Sen. Susan Collins ended weeks of speculation about whether she supports the Iran nuclear deal on Tuesday when she presented a floor speech against it.

Collins has been mum about how she’d vote on the deal since it was announced earlier this summer. For a time, her position was seen as crucial as Democrats and others were tallying votes in the U.S. Senate to determine if a resolution against the deal could pass in the first place and then, whether there would be enough support to sustain a veto by President Barack Obama.

Those calculations ended last week when enough U.S. Senate support was established to sustain a veto, making Collins’ decision largely moot.

The other three members of Maine’s congressional delegation made it clear weeks ago where they stood: 1st U.S. House District Democratic Rep. Chellie Pingree and independent Sen. Angus King in favor of the deal and 2nd District Rep. Bruce Poliquin, a Republican, in opposition.

Collins is widely seen as more moderate than many of her Senate Republican colleagues and was one of seven Senate Republicans who supported starting negotiations with Iran and other nations. She delayed her decision while she studied the issue until Tuesday, the day the Senate began debate of a resolution to scuttle the deal, which has been described by its opponents as being far too lenient and short-sighted.

To date, no Senate Republicans have expressed support for the deal, which also has drawn criticism from Israeli political leaders.

In her speech on the floor of the Senate, Collins called the decision whether to support the deal “one of the most important foreign policy decisions ever to face the U.S. Senate.” She continued to say that she had been hopeful that the Obama administration would craft a deal that would force Iran to outright give up its nuclear program, but that that hasn’t come to pass.

“I have long believed that a verifiable diplomatic agreement with Iran that dismantled its nuclear infrastructure and blocked its pathways to the development of a nuclear weapon would be a major achievement, an accomplishment that would make the world far safer,” said Collins, according to a transcript of her remarks. “Regrettably, that does not describe the agreement that the administration negotiated. The agreement is fundamentally flawed because it leaves Iran as capable of building a nuclear weapon at the expiration of the agreement as it is today.”

Under the deal, economic sanctions on Iran that have been in place for years would be lifted when Iran proves it has removed centrifuges and uranium stockpiles, among other requirements. Iran will be allowed to enrich uranium but only to a level well below what could be weaponized, and the country would allow international inspectors into the country for 15 to 25 years.

Collins said lifting the economic sanctions on Iran, which include restricting the country’s ability to sell oil, would allow it to bolster its military with conventional weapons while it waits for the expiration of the deal now under consideration.

“I do expect that Iran’s leaders will invest in a few high-profile projects to help their own citizens, but given their history, it is inevitable that billions more will be used to finance terrorism and strengthen Iran’s power and proxies throughout the Middle East,” said Collins. “Given its history, there is no question in my mind that Iran will try to cheat on the new agreement.”

Votes on the deal are expected this week in the House and Senate. On Tuesday, there were reports that support for the deal was growing.

Christopher Cousins has worked as a journalist in Maine for more than 15 years and covered state government for numerous media organizations before joining the Bangor Daily News in 2009.