Jose Mourinho is determined to land Wayne Rooney before the transfer window closes and is again ready to test Manchester United's resolve with a bid.

United have so far rejected two bids from Chelsea for Rooney, with manager David Moyes insisting Rooney was not for sale at any price.

Mourinho said he will keep trying to land Rooney despite United's protestations as long as Chelsea do it the right way, similar to the manner in which Barcelona bid for David Luiz this summer.

"You try, because nobody forbids you to try," Mourinho told reporters ahead of the English Premier League clash with Aston Villa.

"When you think that you'd like to have one player and the market is open and the official bids are not forbidden, official bids are always accepted in an ethical way.

"Of course, the player's owners they can do exactly what we did in relation to David Luiz and Barcelona."

This transfer saga has been rumbling on all summer and will continue to do so until the transfer window closes on September 2.

Several managers have come out and said the transfer window should be shut before the season starts, with Newcastle manager Alan Pardew in particular miffed at the way in which his player Yohan Cabaye has been left unsettled by a bid from Arsenal earlier this week.

"At a certain point I agree with what Alan was saying, that the transfer window goes too far, the transfer window goes to the third, fourth fixture of the season, which I also agree that is too much," Mourinho said.

"But at the same time it gives everybody a chance to be in the market while we are winning or losing points.

"We have conditions to try to improve our team by bringing in one more player and we are going to try that till the end."

United are unlikely to sell to one of their direct rivals for their title, especially so late in the transfer window, and the only way this deal is likely to happen, is if Rooney himself vehemently agitates for a move, which again appears unlikely.