START to Stop?
The Obama administration's attempt to reset relations with Russia - a principal foreign policy aim - is in danger of running aground because of difficulties in the US Senate ratifying a nuclear arms agreement.
"A lot is at stake", Anders Fogh Rasmussen the Secretary General of Nato, said in a Newsnight interview today at the Lisbon summit, adding that "early ratification is instrumental" in improving relations with Russia.
In April, the US and Russia concluded the START agreement, limiting their strategic nuclear arsenals.
In order for the treaty to come into effect, 67 Senators must vote for it. Democrat losses in the mid-term elections mean that 14 Republicans must back START and that now seems unlikely.
Jon Kyl, a Republican from Arizona says the Senate should not vote on the treaty this year. By January next year those newly elected members of his party will have taken their seats.
Russian analysts argue that President Dmitri Medvedev has taken considerable political risks in advancing relations with the US, and that if the treaty falters, this progress could be undone.
There has been much discussion on the margins of this summit about the diminishing prospects for the nuclear treaty.
Speaking to us today Mr Rasmussen said the Lisbon summit, "will express the strong desire to see an early ratification of the START treaty".
Some believe that Mr Kyl could be persuaded to withdraw his objections to an early vote if the Obama administration invested more money in the nuclear weapons research facilities that are major employers in Arizona.
Others argue that Mr Obama's opponents are bent on denying him the foreign policy success of improved relations with Russia.