There are rumours that the wife of ousted prime minister Thaksin is seeking a meeting with Prem.
Pojaman met Prem after her husband was overthrown in 2006.
Noppadon insisted Pojaman returned to Thailand to fight corruption charges against her only, and not to play a role in screening potential Cabinet members.
"There is an attempt to discredit the People Power Party by linking it with a nominee of deposed prime minister Thaksin," he said.
Pojaman went shopping on Thursday with children Panthongtae, Pinthongta and Paethongtarn at Gaysorn Department Store.
Meanwhile, Thaksin quietly left Hong Kong on a flight to London Thursday, two days after his wife was arrested on corruption charges in this country, Associated Press reported.
Thaksin has lived abroad since his ouster in the September 2006 coup, mostly shuttling between Hong Kong and London, where he owns an apartment.
Dressed in a dark suit, Thaksin chatted on his mobile phone as he waited in line with other passengers at the Hong Kong International Airport to board his flight.
"He will be going to London," said Noppadon. "I don't know the reason. He's a free man."