The hard was used for installation runs early in FP1 and was quickly abandoned by teams so they could focus on the mediums and softs.

Force India technical director Andy Green summed up the views of the pitlane when he noted: "I think it's so far out of bed for this generation of car, at the moment, I can't see us ever wanting to use it."

Pirelli now looks likely to abandon its original plan to use the hard at Silverstone, having postponed the announcement of its British GP choices until after the Barcelona weekend, when the usual schedule would have seen a decision made by now.

The delay will allow the Italian company to properly assess its data from Spain.

"That's why, for example, we have agreed together with the teams to decide the allocation for Silverstone after Barcelona," F1 technical boss Mario Isola said when asked by Motorsport.com. "If you look at the natural deadline, it was before the race in Barcelona, it was last Thursday.

"We decided to postpone the choice until after Barcelona, to give to the teams more information on the performance in Barcelona.

"The process is usually that we make a proposal that we agree with the FIA. We are going to analyse the data and talk to the FIA. Obviously, we have to have an internal meeting and decide."

Other races where the hard has traditionally been used are Malaysia, Japan and Brazil. As things stand, it is still likely to be chosen for Suzuka, with the expected major increase in downforce and hence loads due to ongoing car development forcing Pirelli to take a more conservative approach.

At the moment, the plan is that it won't be utilised in Malaysia or Brazil, although those choices won't be officially communicated to the teams until the relevant deadlines.

"We are planning to use the hard in Suzuka," said Isola. "Suzuka is in the second half of the season, so we have to wait. The other high severity circuit was Sepang, but last year with the new surface Sepang was less abrasive."

Supersoft choice for Spain "too aggressive"

Inevitably, Pirelli has come under scrutiny as to why it hadn't opted for a medium, soft and supersoft range for this weekend, especially given that the latter compound worked out well in pre-season testing at the same venue.

But Isola says that the fixed allocation across all the teams for the first five races – agreed with the FIA before the new cars hit the track – meant that a late change would have been too dramatic.

"The problem here, with the fixed allocation that was decided last year by all the teams, if we move one step softer it means that we come to Barcelona with two sets of medium, four sets of soft, and seven sets of supersofts.

"Honestly, this is a bit too much, or too aggressive, so we didn't want to oblige the teams to have this compulsory aggressive selection, and this is why we decided to go harder, medium and soft."

Isola admitted, however, that even with a free allocation choice by the teams – which would have meant not everyone would be committed to seven sets of the softest compound – Pirelli would still have brought the hard. This is because the decision had to be made before the first race of the season.

Asked if hards could have been abandoned, Isola said: "Honestly, not. Because when we had to decide the allocation, it was eight weeks ago. It is clear that, if you ask me now, probably I would say yes, but if I decided last week, but not eight weeks ago, when we had just some information coming from the pre-season test.

"So no information on upgrades of the cars, no information on the first four races, and so on. If I say yes for sure, I am not telling the truth."

He acknowledged that the supersoft had worked well in testing, but warmer weather and car development since then meant that a cautious approach was correct.

"It was OK in that condition, with those loads. Now we are here with an estimation of the loads of the pre-season test, with a temperature that is different compared to the pre-season test.

"Some years we have much higher temperatures here. So we have also to consider all this."