April 30 (Reuters) - London's FTSE 100 index rose on Thursday, with upbeat results from

Rolls-Royce and Glencore ( GLCNF ) bolstering sentiment, while rate-sensitive mid-cap stocks rallied after

the Bank of England held its interest rate steady.

The blue-chip FTSE 100 closed 1.6% higher at 10,378.82 points, while the midcap FTSE

250 gained 1.2%, snapping a five-day losing streak.

* Engineering firms were mixed as Rolls-Royce climbed 7.6% after reiterating its

profit outlook, offering the biggest boost to the benchmark index, while Weir Group ( WEIGF )

slid 4% after reporting a fall in first-quarter orders.

* Water utility United Utilities jumped 11.1% to the top of the FTSE 100 after

the company forecast an increase in annual revenue and raised its five-year investment plan.

* Glencore ( GLCNF ) shares added 2.6% after reporting a 19% rise in its first-quarter

copper production, while Irish energy distributor DCC dropped 5.8% after rejecting a

4.95-billion-pound ($6.66 billion) takeover proposal.

* Meanwhile, the Bank of England kept its main lending rate steady at 3.75%, as widely

expectedand set out scenarios for the economic impact of the Iran war.

* "We are still minded to think that the recessionary risks facing the economy will

limit any second round inflation effects ... but if oil prices continue to move higher, it is

hard to see how the Bank avoids having to hike later this year," said Luke Bartholomew, deputy

chief economist at Aberdeen.

* The pound appreciated 0.7% against the dollar, while gilt yields slipped across

the board.

* Global oil prices retreated from a four-year high, but concerns that the U.S.-Iran war

could worsen and lead to a protracted Middle East oil supply disruption lingered.

* Rising crude prices stoked inflation worries, bolstering gold prices, which in turn

lifted shares of precious metal miners by 5%.

* The FTSE 100 is up around 2% this month, far below European and U.S. benchmarks, as

markets view Britain as highly vulnerable to the jump in energy prices due to the country's

heavy use of natural gas.