LONDON (Reuters) - Lewis Hamilton cannot expect an easy ride from new McLaren team mate Heikki Kovalainen next year, according to Briton Jenson Button.

"I'm sure he (Kovalainen) is not interested in just finishing a few races in front, I'm sure he wants to go for the title," the Honda driver told Reuters at the weekend's Race of Champions event.

"He won't hold back just because he's got Lewis as a team mate. I think it's good for both of them."

Kovalainen signed for McLaren last week in what amounted to a straight swap with double world champion Fernando Alonso, who rejoined Renault after a difficult season at the Mercedes-powered Formula One team.

Alonso had complained about McLaren's policy of equal treatment for their two drivers, with the Spaniard expecting number one billing alongside his 22-year-old rookie team mate.

Hamilton, who has been backed by McLaren for the past decade, is expected to lead the team's 2008 challenge after winning four races and finishing overall runner-up by a single point to Ferrari's Kimi Raikkonen.

Kovalainen had a patchier debut season with former champions Renault, looking ragged in his first race but eventually outperforming experienced Italian team mate Giancarlo Fisichella.

He was still surplus to requirements at Renault, who opted to partner Alonso with Brazilian rookie Nelson Piquet junior, and in danger of missing out on a race seat when it seemed McLaren were leaning more towards their Spanish test driver Pedro de la Rosa.

"He's a great guy and deserves to stay in a team," said Button of the Finn. "Having him not racing in Formula One would be wrong. It's great that he's got a drive."

Kovalainen has said he expects equal treatment to Hamilton.

"One thing that I wanted to establish before signing was that I'd be treated equally," he told BBC radio. "I think we can fight on the track as much as we can but off the track we can laugh about it."

Hamilton's father Anthony said he was looking forward to a less controversial year after a season that also saw McLaren fined a record $100 million (49.6 million pounds) and lose all their constructors points for a spying controversy.

"I don't expect any issues with team mates or other teams or drivers," he said.

"We've all had a rough 2007, I think everybody's focus next year will be; "Let's just have a good year whoever wins'. That's what we want.

"Heikki is a decent guy, Lewis is a decent guy, so I'm sure they'll get on well. We've known him for a long time -- Lewis and Heikki raced karts against each other."

(Editing by Miles Evans)