The London market finished in the red as doubts over major banking and pharmaceutical takeovers weighed heavy on the Footsie.
The FTSE 100 Index closed 7.1 points down at 6479.7 as investors were underwhelmed by deals unveiled by Barclays and AstraZeneca and a slow start on Wall Street failed to add late impetus.
Barclays announced it had agreed the terms of a merger with Dutch bank ABN Amro, but the stock was off more than 2%, or 17p, to 733p, as the agreed price came in above expectations and analysts questioned the cost savings estimated by the group.
Royal Bank of Scotland was lower on the Barclays announcement, but finished the day in positive territory after the bank's consortium, which also includes Belgium's Fortis and Spain's Santander, said it had cancelled its scheduled meeting with ABN on news of the Barclays deal. The stock closed 3p higher at 2030p.
Pharmaceuticals firm AstraZeneca led the fallers' board, extending earlier losses to fall more than 4% or 121p to 2832p amid concerns over the £7.6bn (€11.2bn) price it paid for American firm MedImmune.
The fall came despite a solid set of first quarter results and news that the acquisition would significantly boost its product pipeline.
GlaxoSmithKline - due to report first quarter figures later this week - also suffered from the negative sentiment, as its shares fell 22p to 1466p.
Moving in the opposite direction, Scottish & Newcastle topped the risers' board amid renewed takeover speculation after a report said drink giants SABMiller and Diageo held discussions regarding a move for the brewer.
Shares were up nearly 4% earlier in the day but eased back as the rumours cooled later to close 16p ahead at 587.5p.
Oil prices heading towards 65 US dollars a barrel also helped majors BP and Royal Dutch Shell make progress. Shell was 24p ahead at 1789p and BP 7.5p up at 577.5p.
The biggest Footsie risers were Scottish & Newcastle ahead 16p at 587.5p, Hanson up 14p at 841p, Prudential up 12.5p at 754.5p and InterContinental Hotels up 18p at 1242p.
The biggest Footsie fallers were AstraZeneca down 121p at 2832p, Barclays off 17p at 733p, Marks & Spencer down 11p at 709p and GlaxoSmithKline down 22p at 1466p.