German rookie Nico Hulkenberg stunned Formula One's title contenders by seizing pole position for Williams by a massive margin at the Brazilian Grand Prix on Saturday.
Former champions Renault and Williams unveiled their 2009 Formula One cars on Monday before testing at the new Algarve Motor Park circuit in southern Portugal.
Williams join Ferrari, Midland/Jordan, Red Bull and Toro Rosso/Minardi in agreeing to an extension with the F1 chief.
Williams halted a pre-season Formula One test at Barcelona's circuit de Catalunya on Friday after Japanese rookie Kazuki Nakajima crashed the team's new car into the barriers.
Red Bull make changes to car after discussions with FIA
Formula One drivers expressed shock after the sport's governing body quadrupled the amount stewards can fine them to a maximum of one million euros ($1.06 million).
Ferrari made a strong start to the first day of Formula One testing, on Monday, with four-times world champion Sebastian Vettel top of the timesheets at lunchtime with 72 laps completed.
Williams have appointed experienced German racer Adrian Sutil as reserve driver for the season, the Formula One team said on Thursday.
World champion Michael Schumacher qualified fifth fastest for Sunday's Monaco Formula One Grand Prix.
Max Verstappen won the Miami Grand Prix from ninth on the starting grid with a masterful display of tyre management on Sunday.
Red Bull's Max Verstappen started the season with a commanding Bahrain Grand Prix win from pole position.
The Formula One team said the Chennai driver would add 'a vital element' of continuity to the test and development programme in its first year with new engine partner Toyota.
Lando Norris won the season-ending Abu Dhabi Grand Prix on Sunday to deliver McLaren's first Formula One constructors' title since 1998
The final phase of qualifying was halted, with only Piastri and Haas' Nico Hulkenberg having set times, when Sainz slammed backwards into the barriers at the final corner as he prepared to start his flying lap.
Williams pushed their luck and paid the price in Sunday's Spanish Formula One Grand Prix as Juan Pablo Montoya and Ralf Schumacher wrestled with brake problems.
Susie Wolff made her full test debut with former champions Williams on Friday, the biggest step by a woman driver in Formula One for more than 20 years, with race regulars paying her compliments.
Williams provided a first glimpse of their new Formula One car with a confident prediction that it would be good enough to move the former champions back up the grid after a dire 2013 campaign.
Frank Williams said the FW25 is a completely new race car, shorter than lasy year's.
Williams will revert to older versions of their front wing in Turkey this weekend after both of the Formula One team's cars crashed at the last race in Monaco.
Valtteri Bottas has denied signing a pre-contract with Ferrari, saying he was amused by some of the speculation about his Formula One future.
Red Bull's triple World champion Max Verstappen wrapped up a year of unprecedented dominance with his record-extending 19th win in 22 races at the season-ending Abu Dhabi Grand Prix on Sunday.
It was the first time this season that Mercedes had failed to take pole and Sunday's race will be Williams's first start from the front of the grid since Venezuelan Pastor Maldonado in Spain in 2012.
McLaren are leading the constructor's championship but are only 29 points ahead of Ferrari, with Leclerc an obvious threat and team mate Carlos Sainz qualifying fifth and Mercedes' George Russell sixth.
No woman has competed in Formula One since 1976 but organisers of the 'W Series' hope to provide a platform for them to develop skills before taking on the men further up the motorsport ladder. The idea of an all-female series is not new but has been controversial in the past, with top women racers adamant they want to compete against the men rather than be separated.
'I think you can assume that (the new contract will be signed),' the German said.
'I was actually with Serena last week in LA ... she came out to Mexico (for the race) which for me was a real honour to have someone of her power, someone who has achieved so much' 'Venus talks a lot about wisdom and about her growth and about the process of being a sportsman or sportswoman so generally from both of them, I take a lot of inspiration and admire them both hugely'
The shocked 21-year-old rookie was unhurt in the incident between turns two and three but Williams said the chassis would have to be replaced, sidelining the Briton until Saturday's final session before qualifying. Former world champions Williams are already facing plenty of problems with an uncompetitive car that is some way off their rivals' pace.
Hulkenberg is the team's reserve driver and has stood in for them three times already since he last raced full time in Formula One with Renault in 2019.
"I'm convinced that we have made a step forward but I don't know how big this will be until we get to Montreal," Ralf Schumacher said.
Max Verstappen added his name to the list of triple Formula One World champions on Saturday after Red Bull team mate and sole title rival Sergio Perez crashed out of the Qatar Grand Prix sprint race.
World champion Max Verstappen got back to winning ways on Sunday with a third straight pole-to-flag victory at the Japanese Formula One Grand Prix, leading teammate Sergio Perez across the line for a Red Bull 1-2 at Suzuka.
Britain's George Russell will stand in for Lewis Hamilton at Mercedes for Sunday's Sakhir Grand Prix after being released by Williams.
Charles Leclerc won the US Grand Prix in a Ferrari one-two with Carlos Sainz on Sunday as Formula One championship leader Max Verstappen dealt Lando Norris a significant setback in their title battle.
