Activist investor Olivant has raised its stake in Swiss bank UBS to 2.5 percent and said on Wednesday it had fully supported the recent rights issue.
"Olivant ... now holds 2.5 percent of the ordinary share capital of UBS, thereby demonstrating its belief in the potential restoration of shareholder value achievable through decisive action on the part of the UBS Board," the group said.
Olivant, headed by former UBS chief executive Luqman Arnold, said in April it had taken a 1.1 percent stake and called on the Swiss bank to reform and consider splitting up.
It has gradually increased that holding and said on Wednesday it welcomed and supported a number of the recent decisions and actions being taken by the board, and was engaged in a "constructive dialogue" with the chairman and some board members.
It said there remained an urgent need to clarify future strategy to allow UBS to attract and retain talented bankers.
UBS wrapped up a 16 billion Swiss franc rights issue last week, with 99.4 percent of the rights taken up in the bank's second effort to revive finances ravaged by the global markets crisis.
The bank, once a rock of Swiss financial prowess, is now Europe's biggest casualty of the global crisis triggered by risky U.S. home loans.
It has written $37 billion off dud investments -- twice that of Royal Bank of Scotland.
Olivant's move contrast with that of other shareholders, such as Frankfurt Trust, which has pared back its stake in UBS.