UK government bonds dropped sharply on Friday after Andy Burnham's special election victory reignited political uncertainty and raised questions about fiscal direction. The former Manchester mayor's win in Makerfield clears his path to challenge Prime Minister Keir Starmer, leaving investors anxious about potential policy shifts ahead.

Ten-year gilt yields climbed five basis points to 4.81%, lagging European peers amid a broader bond market selloff. Oil prices topping $80 a barrel added inflationary pressure, while the UK's debt burden is projected to reach 105.4% of GDP by 2027 - up from 98.8% in 2023. Market watchers fear any move toward left-wing policies could spook investors.

Bond markets appear to be pricing in caution rather than panic. Burnham has attempted to moderate his previous criticism of the government's economic approach, though his lack of detailed policy proposals leaves borrowing costs vulnerable. Investors recall the 2022 Liz Truss unfunded tax cut debacle that triggered a historic gilt rout.

The episode underscores how the UK's fiscal credibility remains hostage to political stability. With Starmer's government already walking a tightrope on spending discipline, any leadership challenge risks reopening wounds in debt markets that took months to heal.