LONDON, ENGLAND - AUGUST 20: England captain Andrew Strauss reacts after losing the 3rd Investec Test match between England and South Africa at Lord's Cricket Ground on August 20, 2012 in London, England. (Photo by Gareth Copley/Getty Images)

London - Andrew Strauss was on the brink of resigning as England's Test captain according to reports in the British press on Wednesday in the latest twist to the Kevin Pietersen saga that has rocked the side.

If Strauss does step down, after three years in charge, his Test opening partner Alastair Cook, already England's one-day captain, would be the obvious choice to succeed him as skipper in the five-day format.

After England lost their number one Test ranking to South Africa following a 51-run defeat by the Proteas at Lord's earlier this month that took place almost a year to the day since they ascended to top spot, Strauss was uncertain regarding his future

“It's probably hard to answer that after the week that's just gone by. It's been a tiring week,” said Strauss after what was his 100th Test.

“We all need to sit down - myself and (coach) Andy Flower in particular - and try and map out the way forward,” added the left-hander, who reached his century of Test appearances on his Middlesex home ground.

Talk of a “tiring week” was a direct reference to England's decision to drop Pietersen, who hasn't played international cricket in any format since making 149 in the drawn second Test at Headingley after he admitted sending “provocative” texts to South African players.

Some of these were alleged to have been critical of Strauss, who succeeded South Africa-born and raised Pietersen as England captain in 2009.

Speculation about Strauss's future intensified Tuesday.

The 35-year-old was set to play for Middlesex against Worcestershire in a County Championship match starting Tuesday but was withdrawn from the side as Pietersen reminded England of what they were missing with a superb 163 for Surrey against Somerset.

And a couple of hours after the England one-day team suffered an 80-run thrashing by South Africa in Southampton later Tuesday, the England and Wales Cricket Board (ECB) announced that managing director Hugh Morris would be holding a press conference at Lord's at noon (1100 GMT) on Wednesday.

Meanwhile ECB chairman Giles Clarke was due to give a separate media briefing at Derby at 2pm on Wednesday.

The ECB refused to say anything on Tuesday other than issue a brief statement giving the details of Morris and Clarke's respective news conferences.

Strauss, 35, has enjoyed modest returns with the bat in recent years and his 122 against the West Indies in May was his first Test century since November 2010.

He followed up with another century, his 21st and one shy of the England all-time record, at Trent Bridge but averaged just 17.83 in six innings against the South Africans.

England's form in 2012 has been poor, with six defeats in 11Tests culminating in a 2-0 series loss to South Africa, their first home reverse in four years.

Were Strauss, who has led England to home and away Ashes series wins, to resign the Test captaincy he would be the third England skipper to be 'seen off' in as many tours of England by South Africa captain Graeme Smith.

Nasser Hussain resigned during the England-South Africa series in 2003, Smith's first series as Proteas skipper, with Michael Vaughan standing down five years later.

Smith, who made 52 against England in Tuesday's one-dayer, remains the Proteas' Test captain but the one-day side is now led by AB de Villiers.