City travel to the City Ground on Saturday to play Notts Forest (3:00pm) before returning to entertain Derby County on Bank Holiday Monday in the live Sky game (5:35pm).
"Unfortunately our preparations for next weekend will be disrupted because of international calls which have come at the wrong time for us," said Lawrence.
"To have international games before a bank holiday weekend when we have two games in three days is the height of lunacy. To be fair it's not the result of Wales or the players.
"The match against Serbia was postponed and there was no alternative but to play it this week. But from Cardiff City's point of view it is disappointing to be without so many of our players in training this week".
"It's the price we have to pay for having such quality players at our club."