GENEVA, (Reuters) – The United States and Russia  pledged yesterday to rebuild their strained relations and  launched a plan to reach agreement on strategic nuclear missiles  by the end of the year.

U.S. Secretary of State Hillary Clinton and Russian Foreign  Minister Sergei Lavrov, meeting in Geneva, agreed to find common  approaches on Iran, Afghanistan and North Korea.

They discussed areas of disagreement, too, from human rights  to Georgia, where Russia fought a short war in 2008 over a  breakaway region, and Kosovo, whose independence is recognised  by the West but not by Russia.

Clinton said after the meeting it would take time to rebuild  the relationship and this would require “more trust,  predictability and progress”.

Their differences did not overshadow the talks, which marked  a further stage in President Barack Obama’s efforts to reach out  to other countries and make U.S. diplomacy more effective.

“We exchanged our vision of immediate priorities in our  relations. I am convinced, and the secretary of state will share  my opinion, these priorities largely coincide,” Lavrov told a  news conference.

Symbolising Obama’s intention to improve relations, Clinton  presented Lavrov with a small box bearing a red button marked  “reset”, and the overall tone was conciliatory, with Clinton and  Lavrov joking with each other on first-name terms.

“This is a fresh start not only to improve our bilateral  relationship but to lead the world in important areas,” Clinton  said.

Lavrov said Russia and the United States would work honestly  and openly together even on areas of difference.

“We understood that our bilateral relations are getting a  chance today we cannot afford to miss,” he said.

The tone was in contrast to relations under Obama’s  predecessor George W. Bush, strained by issues including  Russia’s 2008 military intervention in Georgia and U.S. plans to  build a missile interception system in eastern Europe.

Both ministers agreed to work together on a range of issues.  Clinton said the priority was a new treaty on strategic arms.

The United States wanted to reach agreement by the end of  this year, when the Strategic Arms Reduction Treaty (START I)  expires, she said. Lavrov called the 1991 pact “obsolete”.

Clinton said they wanted to present a plan to Obama and  Russian President Dmitry Medvedev before they meet at the G20  summit in London on April 2, so they could agree on instructions  to be given to negotiators.

Besides trying to reduce their own arsenals, the two powers  agreed to work together to prevent nuclear weapons spreading.

“The most serious threat facing humanity … is a potential  nuclear weapon in the hands of an irresponsible actor. Both  Russia and America know that we have to work together to try to  prevent that,” Clinton said.

Lavrov said Moscow and Washington would try to reach  agreement soon on how to deal with the nuclear programmes of  Iran and North Korea.

He also sought to assuage U.S. concerns about Iran’s  interest in buying Russian S-300 air defence systems, which  could help repel possible Israeli or U.S. air strikes.

Clinton said the United States was reviewing its policy  towards Iran and would welcome Russian advice on how to prevent  Tehran from acquiring nuclear weapons or supporting terrorism.

The two agreed to work on Afghanistan, where Obama is  considering beefing up U.S. forces and where Moscow fears  Taliban insurgency may spread Islamist militancy towards Russia.

Russia and the United States would cooperate on preparing a  U.S.-sponsored conference in Afghanistan, Lavrov said.