President Mahinda Rajapakse, under pressure over allegations that his troops have been shelling civilian areas, spoke to Ban on Tuesday evening.
The president told Ban that with a visit he would "then be able to make a better assessment of the conditions faced by Tamil civilians" because of the fighting with the Liberation Tigers of Tamil Eelam (LTTE).
The United Nations last month said that the government had refused a request to visit the combat zone, where it estimates some 50,000 people are still being held by the Tigers as a human shield.
It was not immediately clear if the government had changed its stance and if it would allow Ban to travel to the conflict area, where thousands of troops have encircled the remaining Tigers.
The Sri Lankan government has invited UN officials and other diplomats for assessment missions in the past but has tightly restricted their movements -- ostensibly for security reasons.
The UN's top humanitarian relief official John Holmes failed to sec