By Francis Markus BBC

The draft law sparked a massive demonstration by half a million people on 1 July, which Mr Tung said had left him sleepless.

It may still be too early to say how much of a breakthrough this pledge of further consultation represents from the point of view of the bill's opponents.

Tung Chee-hwa's critics are increasingly assertive

Much will depend on the manner in which the bill is handled. The choice of a new Security Secretary to replace the controversial Regina Ip, whose resignation was announced on Wednesday, will also be crucial.

Critics of the existing bill said the legislation threatened press freedom and political and religious rights. Mr Tung was forced to put the bill on hold in the face of massive opposition, when one of his key legislative allies, James Tien of the Liberal Party, resigned from the cabinet.

On Thursday, Mr Tung told journalists he had no intention of resigning.

But it is still not clear whether Mr Tung's position has been strengthened or further undermined by Ms Ip's resignation, and by the resignation a few hours later of Financial Secretary Antony Leung.

Some opposition politicians have welcomed the departure of Ms Ip, a key figure behind the controversial bill.

Yeung Sum, Chairman of Hong Kong's Democratic Party, said Ms Ip's resignation could open the way for more consultations on the proposed security law.

Popular anger

But others have repeated their calls for Mr Tung himself to step down, a refrain also taken up in the media.

"The top officials have stepped down, what about the chief executive?" said a headline in the anti-Tung mass-circulation Apple Daily newspaper, which has played a key role in the campaign.

Ms Ip and Mr Leung have been among the key targets of public anger in the protest campaign.

ARTICLE 23 BILL Outlaws: Reporting state "secrets" Criticism of Beijing authority Access to "subversive" material Threatens currently legal groups, such as Falun Gong Q&A: HK's anti-subversion law

Many analysts had seen their departure as the minimum sacrifice that Mr Tung would need to offer to assuage popular anger with his administration over a range of political and economic issues.

But it is not clear whether it will achieve that aim. There has already been criticism of Mr Tung's handling of the resignations.

He said on Wednesday that Ms Ip offered to resign for personal reasons before the 1 July protests, although he tried to persuade her to change her mind.

Mr Leung left meanwhile amid news that he could face prosecution over buying a luxury Lexus car earlier this year shortly before raising vehicle taxes.

The head of the pro-Beijing Democratic Alliance for the Betterment of Hong Kong, Tsang Yok-sing, said it was well known that the security chief had wanted to resign and go abroad with her daughter, and the financial secretary had been under great pressure over the car-buying scandal.

But Mr Tsang rejected suggestions of a vacuum in the government.

"I believe that a new secretary for security will be announced very soon. As for the financial secretary, we know that it is not easy to find someone who is well qualified, who has credibility and also who is willing to take the job. I'm afraid it will take some time before a replacement can be found," he said.

Mr Tung travels to Beijing on Saturday to brief Chinese leaders on the crisis.

How he and they handle the security bill and demands for reform, will be crucial to how Hong Kong's volatile situation evolves.