Gordon Brown has shaken hands with Alex Salmond for the first time in their new roles, declaring that he will work with him for Scotland's "prosperity".
Mr Brown and Mr Salmond met at the talks in Belfast
The prime minister and Scotland's first minister were attending a British-Irish Council meeting at Stormont in Belfast.
They were the first official talks the two men have held since becoming the UK and Scottish government leaders.
Scottish Executive sources have said they want an "appropriate relationship" with Westminster.
Entering the talks, Mr Brown said: "I look forward to working with Mr Salmond for the prosperity of the people of Scotland."
Northern Ireland First Minister Ian Paisley was also at the meeting.
Mr Salmond's talks with Mr Brown followed his meeting on Friday with Minister for Justice Jack Straw.
This has been given as an example of a "co-operative" approach in action.
Mr Salmond was also in conciliatory mood, welcoming Mr Brown's presence at the meeting.
He rejected suggestions that the council was an opportunity for the devolved administrations to combine together to exert pressure on the government in London.
Mr Salmond said: "It is how we co-operate as administrations across and around these islands in the interests of the people. I think that is an entirely positive agenda."
He has called for greater dialogue between Westminster and the devolved administrations.
Mr Salmond wants the re-establishment of joint ministerial committees, set up in 1999 to encourage co-operation between London and the devolved governments.
The plenary joint ministerial committee has not met regularly in the past five years.
Also attending the British-Irish Council was Irish Taoiseach Bertie Ahern.
The council is designed as a forum for talks between Westminster, the devolved UK administrations and Ireland.