The International Cricket Council has given India until midday on Friday (0630 GMT) to confirm whether they intend to play Virender Sehwag in the first Test against England in Mohali.

The ICC's chief executive, Malcolm Speed, gave the ultimatum to the Board of Control for Cricket in India in a letter which has been published on the ICC website.

And in a press conference at Lord's cricket ground this afternoon, Speed left no room for doubt about the severity of the situation.

He warned: "It's fair to say that the ICC and the BCCI are on a collision course and the consequences for world cricket are of great significance.

"At least the good thing about being on a collision course is to know that you're on it before you collide. We have some time up our sleeve and we'll use that as productively as possible."

"I think there's a direct challenge to the authority of the ICC as the governing body of the sport," Speed said.

"If we had overturned the decisions of the referee, taken him out of the match or vacated the penalties, it would have been an invitation for that to happen the next time any board is unhappy at decisions.

"We've already cancelled the status of one Test match. I believe that's unprecedented and I don't want to see it happen again because every time we do that, we damage the game.

"People who want to watch great cricket matches are deprived of the opportunity of doing that. Cricket boards that have entered into contracts with media outlets and sold tickets would lose revenue.

"There has been damage done already but cricket has come through a difficult time over the past 12 to 18 months with corruption inquiries and I'm sure it will come through this."

In his letter to the BCCI President, Mr Speed expresses his concerns about the possible threat to the safety of the players and public if the decision on Sehwag is delayed until the start of the Test.

Speed writes: "If this issue is not resolved well ahead of the Match, it is possible that it will take place at the start of the Match in a highly charged and volatile environment that will exacerbate risk of injury."

Speed also voices concerns about the damage the dispute over Sehwag is doing to the game, and expresses the hope that the Test series against England will go ahead as planned.

"It is important that the series continue and that all matches have Test match status," he writes. "It is (also) important that we avoid any further damage to the game by resolving this dispute as soon as possible."

The head of India's five-man selection committee, Chandu Borde, has effectively been given a free hand to select Sehwag by the BCCI.

"We will be selecting the team on merit," insisted Borde, who will announce the 14-man first Test squad tomorrow.

"As far as I am concerned he is available. There is no directive from the cricket control board. I am under no pressure at all because we are going to select players on merit. There is no pressure on me or the selection committee."

"The issue as to whether he is available for selection is for the board and not the selection committee. We just select the players," said Borde.

"Whether the Test series goes ahead, it's up to the board to decide. We will discuss him (Sehwag) and all the young players that have played against the tourists so far."

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