US President George W Bush nominated John Roberts to replace William Rehnquist as Supreme Court chief justice yesterday, following Mr Rehnquist's death at the weekend.
Mr Bush urged the Senate to confirm the appointment of Mr Robert before the top US court begins its term in October.
Mr Roberts, who is aged 50, could shape the court for decades to come. Mr Rehnquist was 80 when he died on Saturday, having served on the Supreme Court for 33 years and been its leader for 19 years.
The swift appointment by Mr Bush would promote to the Supreme Court's top job a newcomer who is currently being considered for a post as one of the eight associate justices.
It would also ensure a full nine-member court, because retiring Justice Sandra Day O'Connor has said that she will remain in the job until her replacement is confirmed.