"The top four next year will be the same top four as this year," he added.
"What I can say to the Newcastle fans is that we will be trying to get fifth and we will be trying to win the other league that's going on within the Premier League.
"I haven't got enough money and I wouldn't be able to get the players anyway (to do any better than that), so I will soldier on with what I've got and maybe add one or two, maybe three, depending what's available."
Keegan turned Newcastle into title contenders when he managed them from February 1992 until January 1997 but he feels it is not possible to do the same again.
His opinion was reinforced during the Bank Holiday game against Chelsea, who clinched the win to move level on points with Manchester United at the top of the table ahead of the final game of the season.
"I thought, 'What can I do next year to get near them' and the truth is there's nothing I can do at all," stated Keegan.
It is frustrating that Modric, like Woodgate before him, should take less money than we offered to move to the bright lights of London and European football with Tottenham next season
Newcastle chairman Chris Mort
"I was looking around thinking, 'who can I bring on' and I'm seeing (Andriy) Shevchenko and (Frank) Lampard coming on and Joe Cole thinking about coming on."
Keegan has, however, been promised funds to attract big-name signings.
"Over the summer, we will look to strengthen the squad further," said chairman Chris Mort.
"In addition to immediate fixes, we will want to acquire players that can help make Newcastle United a top team for the medium and long term."
Newcastle have already missed out on the signing of midfielder Luka Modric, who rejected a lucrative offer to join Tottenham instead, just as Jonathan Woodgate did in January.
But Mort is confident that Newcastle are heading in the right direction and that they will soon be in a position to attract players like the 22-year-old Croatian international.
"It is frustrating that Modric, like Woodgate before him, should take less money than we offered to move to the bright lights of London and European football with Tottenham next season," conceded Mort.
"But these are the sorts of difficulties that should get easier to address once we build a squad that competes at the right end of the table."
And Keegan is positive he will get the funds he needs from owner Mike Ashley to improve his squad, saying: "I have no proof of that yet but I have no doubts he will (back me).
"If I can get three or four players in to add to what I have got here - and we have that bit of luck you need with no injuries to key players - then we might be able to win the second division of the Premier League."
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