Johnston: 'Palin wanted to adopt grandson'

The father of Sarah Palin's grandson has claimed that the former Alaskan governor wanted to adopt his baby so people would not know that her teenage daughter was pregnant.

Speaking to Vanity Fair, aspiring model and actor Levi Johnston claimed that the politician devised the plan after discovering that 17-year-old Bristol was expecting.

"She was nagging - she wouldn't give it up. She would say, 'So, are you gonna let me adopt him?'" he claimed.

"We both kept telling her we were definitely not going to let her adopt the baby. I think Sarah wanted to make Bristol look good, and she didn't want people to know that her 17-year-old daughter was going to have a kid."

Johnston, 19, is reported to have fallen out with the Palins following the birth of Tripp in December, with the family accusing him of neglecting his duties as a father. He has accused them of limiting his access to his son.

Palin has yet to respond to the allegations.