Jenkins is trying to restore Barclays' reputation since the revelation of its role in a global interest rate rigging scandal led to a $450 million fine and the departure of his predecessor Bob Diamond.
Those efforts are unlikely to be a straight road.
The Financial Times reported on Friday that British authorities are looking into an allegation that Barclays lent Qatar money to invest in it as part of a rescue fundraising at the height of the 2008 financial crisis.
UK rules forbid a public company from giving financial assistance in order to acquire its shares or those of a parent company.
A Barclays spokeswoman said: "Both the FSA and SFO investigations are ongoing and, as such, we are unable to comment further".
The FSA, SFO and Qatar Holding declined to comment.
Jenkins, who became CEO in August, said he did not want to be considered for a bonus after a difficult year for the bank and its stakeholders.
"I think it only right that I bear an appropriate degree of accountability for those matters," he said in a statement.
He said he was aware of considerable speculation about his bonus and wanted to avoid "further unnecessary public debate". His annual salary as CEO is 1.1 million pounds and he could have received an annual bonus of up to 2.75 million.
RBS CEO Stephen Hester said last June he would waive his bonus for 2012 following a computer systems failure which caused disruption to millions of its customers.
Qatar Holding, which according to the FT is not accused of any wrongdoing, invested 5.3 billion pounds in Barclays in June and October 2008, helping it avoid a government bailout, unlike rivals Lloyds Banking Group and Royal Bank of Scotland.
The Financial Services Authority (FSA) and Serious Fraud Office (SFO) have been looking into the investment since July. Allegations of a loan to the Qataris are a new thread of the investigation, the FT said, citing two sources familiar with the situation.
The deal with Qatar was questioned from the outset. Shareholders were angry it was offered more attractive terms than existing investors. A sale of warrants in November left Qatar sitting on a gain of 1.7 billion pounds from its investment, according to Reuters estimates.
Qatar Holding, part of the Qatar Investment Authority, which was set up by the state in 2005 to diversify its investments away from oil and gas, is the bank's biggest shareholder with a 6.7 percent stake.
Barclays said in August that Britain's fraud prosecutors had launched a criminal probe into payments between the bank and Qatar, a month after revealing the FSA's investigation into dealings between the two parties.
It said the FSA probe was into the bank and four current and former senior employees, including finance director Chris Lucas. Sources have said another is Roger Jenkins, the main architect of the Qatar fundraising who left Barclays in early 2009 and is now at Brazilian investment bank BTG Pactual.
Neither Lucas nor Jenkins immediately responded to requests for comment.
Barclays said in July when it first disclosed the investigation that it considered it had satisfied its disclosure obligations.
Copyright @ Thomson Reuters 2012