The European governing body also repeated its determination to stamp out reckless spending one day after the end of the January window which saw Liverpool and Chelsea pay 130 million pounds between them for just four players.
"There is no doubt that transfers made now will impact on the break-even results of the financial years ending 2012 and 2013 - the first financial years to be assessed under the break-even rule," UEFA said in a statement.
"The clubs know the rules and also know that UEFA is fully committed to implementing them with rigour."
UEFA, worried about the health of club finances, introduced its Financial Fair Play plan last year to try and stop clubs spending more than their generated revenue.
Clubs who fail to comply could be barred from European club competition from the 2014/15 season. They will be monitored over the previous three financial years before being admitted.
UEFA said again it believes clubs are backing its efforts.
"The UEFA Club Licensing and Financial Fair Play Regulations have been widely supported by all clubs and stakeholders, during the long and considered consultation and approval process," added the statement on UEFA's website.
"UEFA is aware of the recent transfer activity across Europe.
BOOK BALANCING
"It must be noted, however, that the financial fair play rules do not prevent clubs from spending money on transfers themselves but rather require them to balance their books at the end of the season.
"It is therefore difficult to comment on any individual situation without knowing the long-term strategy of each club."
UEFA president Michel Platini had previously insisted that some of the biggest-spending clubs, including Chelsea and their Premier League counterparts Manchester City, support his plan.
The European Club Association, whose 197 members include all of the region's biggest clubs, also insist the plan has unanimous backing from its members.
Platini said last month he would not shy away from enforcing the rules even if it meant keeping a big club out of European competition.
"If a club doesn't fall in line and live by the same rules as everyone else, they will have to live with the consequences," he said. "It will be time for them to face the music."
The clubs' recent behaviour, however, appears to contradict claims they were trying to bring their finances under control.
Manchester City's squad is so bloated they have 15 players out on loan with a collective price tag of nearly 100 million pounds and there is no hint of a need to balance the books.
Chelsea announced a loss of 70.9 million pounds on Monday but, far from worrying about that figure, issued a statement stressing the good news that they were "cash positive".
Hours later they splashed out moe than 70 million pounds on striker Fernando Torres from Liverpool and defender David Luiz fro
