Section 2--609. Right to Adequate Assurance of Performance

(1)  A  contract for sale imposes an obligation on each party that the
  other's expectation of receiving due performance will not  be  impaired.
  When  reasonable  grounds  for  insecurity  arise  with  respect  to the
  performance of either party the other may  in  writing  demand  adequate
  assurance of due performance and until he receives such assurance may if
  commercially  reasonable  suspend  any  performance for which he has not
  already received the agreed return.
    (2) Between merchants the reasonableness of grounds for insecurity and
  the adequacy of any assurance offered shall be determined  according  to
  commercial standards.
    (3)  Acceptance of any improper delivery or payment does not prejudice
  the aggrieved party's right  to  demand  adequate  assurance  of  future
  performance.
    (4)  After  receipt  of a justified demand failure to provide within a
  reasonable  time  not  exceeding  thirty  days  such  assurance  of  due
  performance  as  is  adequate  under the circumstances of the particular
  case is a repudiation of the contract.