"It was just too fast, too soon for Jason. He didn't like the pressure Britney and her family were putting on him to put a ring on her finger. He told Britney repeatedly that he would never marry, but she refused to believe him," a source told National Enquirer magazine.
Britney, who has sons Sean Preston, three, and Jayden James, two, with ex-husband Kevin Federline, thought she could change his mind by having a baby with him. "Jason told Britney he needs time to chill away from her. She's heartbroken," said the source.
Although the couple have now separated, the 'Womaniser" star was seen wearing a diamond ring on her engagement finger while shopping in Beverly Hills last week. Recently, it was claimed that Britney, who was first romantically linked to Jason in March, was so determined to marry Jason that she was planning to convert to Judaism for him.