The decision of Sri Lankan President Chandrika Kumaratunga to impose a state of emergency is the latest incident in the bitter rivalry between her and Prime Minister Ranil Wickramasinghe.
The divisions between the pair have driven Sri Lankan politics for more than a decade, but have become even more apparent since the last general election in December 2001.
Mr Wickramasinghe's United National Party (UNP) won that election, partly on a mandate to curb the powers of the president.
The PM and president struggle with the division of power
Mr Wickramasinghe had lost to Mrs Kumaratunga in the presidential elections two years earlier, a result many believe was swayed by a sympathy vote.
A Tamil Tiger suicide bomber had blown himself up close to Mrs Kumaratunga on the last day of the election campaign, seriously injuring her and killing more than 30 others.
The new president quickly invited Norway to act as peace mediators, but her approach to Oslo - and the Tigers - gradually hardened.
However, at the same time the Sri Lankan people, tired of the civil war, began to demand a fresh impetus to the peace process, and support for the UNP grew.
When Mr Wickramasinghe defeated the president's People's Alliance in the general election, the pair were forced into an intensely difficult period of co-habitation.
Sympathy votes after a suicide blast helped sway the presidential poll
As Mr Wickramasinghe pushed forward the peace moves, Mrs Kumaratunga consistently railed against giving too much ground to the rebels.
As soon as the ceasefire was announced in February last year, the president accused the prime minister of rushing into a truce that compromised national security and sovereignty.
As peace talks got under way, her party said it was unacceptable for a prime minister's envoys to sit at the same table as the Tamil Tigers.
The People's Alliance has at regular intervals also attacked the role of the Norwegian mediators - on one occasion this year calling them "salmon-eating busybodies".
The president has sent letters of complaint to Oslo, ranging from accusations of bias against Norwegian monitors to discontent over the handing of radio equipment to the Tigers.
On the latter occasion, Mr Wickramasinghe warned Mrs Kumaratunga publicly not to antagonise Norway.
The BBC Sinhala service editor, Priyath Liyanage, says animosities between the two leaders were simmering below the surface even as they shook hands in public.
Mr Wickramasinghe's policy has been to continue his work ignoring the president where possible.
At the same time, members from both sides have been working
to oust their leader's rival.
Mrs Kumaratunga has always said she supports peace moves, but her fear of granting too many concessions means that her power dissolve parliament and call new elections is always hanging over the process.
Mr Wickramasinghe has not had it easy with the Tigers either; they accused him of dragging his feet over peace promises in the north and east - so much so that they pulled out of talks in April.
In trying to bridge the gap, Mr Wickramasinghe can probably call on the support of the business sector, following his successes in the economic sphere.
But with the possibility of a snap election now looming, he may have to obtain a new mandate from the people to press on with the peace process.
Even if he does, Mrs Kumaratunga's presidency will continue until 2005, so there is little sign the rivalry is about to end soon.