North Korea Tuesday repeated calls for a peace pact on the Korean peninsula, days after it fired its artillery near the tense border, but Seoul said Pyongyang wanted a pretext to shun nuclear negotiations. "We and the United States still remain technically at war. Nobody can guarantee that there will be no artillery fired in a war on the Korean peninsula, where (only) the armistice continues," said the North's communist party newspaper Rodong Sinmun. "The United States should accept our (peace treaty) offer sincerely," it said, according to a Korean-language report on the official news agency.Tensions rose last week when the North -- in what it called a routine exercise -- fired around 370 shells over three days near the disputed maritime frontier with South Korea after declaring "no sail" zones.Seoul's military was watching Tuesday for possible short-range missile tests after the North banned shipping from several more coastal zones elsewhere. Related article: SKorea watches for new NKorea missile tests