Tottenham Hotspur manager Mauricio Pochettino conceded his club cannot compete with the two Manchester rivals, who are level on points at the top of the Premier League, in the transfer market.
Pochettino's side face struggling Bournemouth at Wembley on Saturday, hoping to close the five-point gap to leaders Manchester City and second-placed Manchester United.
The top two both spent heavily during the recent transfer window and Pochettino concedes the financial strength of City and United means teams like Tottenham are forced to adopt a different strategy in the market as they attempt to keep pace.
"The difference these days between clubs in the Premier League is that there are clubs, like City and United, who sign who they want and when they want," the Argentine told beIN Sports. "Then there are big teams, like us, who sign when we can and who we can. It's the big difference today."
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Tottenham headed into the international break having maintained their perfect league record on the road with a win at Huddersfield Town.
At their temporary home of Wembley, however, Pochettino's men have continued to struggle, claiming just two points from their three home games in the Premier League so far.
Anything less than victory over a Bournemouth side lying second-bottom will be viewed as a major disappointment.
Pochettino will be hoping Harry Kane can extend his prolific scoring run.
The striker – nominated for the Ballon d'Or this week - has scored 15 goals in his last ten games for club and country, including the winning goals in England's back-to-back 1-0 World Cup qualifying victories over Slovenia and Lithuania last week.
Kane was joined on England duty by club teammate Harry Winks, who will hope the experience of his first international call-up can help boost his chances of more regular action for his club.
And defender Jan Vertonghen returns to club duty having become the most-capped Belgium player of all time when he made his 97th appearance in the 4-0 defeat of Cyprus.
"If you look at him when he arrived at Spurs he was doing well but if you compare it to now, obviously he's played a lot of games in the Premier League and this translates to playing in the national team as well," said Mousa Dembele, Vertonghen's teammate for club and country.
"It's an unbelievable achievement. If you see all the times he's played for Belgium, I can't remember him having a bad game."
Bournemouth manager Eddie Howe believed his side deserved more than a point from the scoreless draw with Leicester City last time out.
The Cherries paid the price for their failure to make more of a number of chances and the sight of Callum Wilson scoring twice for the club's under-21 side this week will have been welcomed by Howe.
Wilson is recovering from a long-term knee injury and while he is still some way off a first-team return, the striker is confident his recovery is going to plan.
"It's always good to score as it builds confidence and since the injury it's good to get back on the scoresheet," he said.
"I was never in doubt over my abilities and I feel I'm striking the ball probably better than I was before to be honest.
"Two goals, both different goals today, and now I'm looking forward to scoring these goals in the first team.
"I'm feeling fine, the knee feels strong and I feel ready to go now. I'm going to carry on working hard in training and waiting for my chance."