The British Prime Minister David Cameron and the French President Nicolai Sarkozy have received a hero's welcome on a visit to Libya while they promised to help finish the job of bringing peace to the country. They are the first foreign leaders to go to Libya since Col. Gaddafi was forced from power.Speaking in Tripoli, they said, the NATO mission will continue until the pro-Gaddafi forces have been defeated. Later the two leaders addressed cheering crowds in Freedom Square in Benghazi. Mr. Cameron praised their fight for freedom.Meanwhile, Libya's interim authorities say, their fighters have entered the coastal city of Sirte, one of the last places still loyal to ex-leader Muammar Gaddafi. A National Transitional Council spokesman said, the fighters had breached Sirte's defences but were meeting heavy resistance there.